From BRT to Multimodality: A Cost-Efficiency Comparison of Public Transport Systems in Curitiba and Lisbon

Abstract

This article conducts a thorough comparative analysis of public transport systems in Curitiba and Lisbon, focusing on cost-efficiency and structural performance from the user’s viewpoint. Curitiba is noted for pioneering the BRT model in the 1970s, while Lisbon is evolving towards a multimodal system with substantial investments in integration and user-centric policies. Employing a case study methodology and mixed analytical approaches, the analysis examines governance structures, network architecture, financing mechanisms, and service quality indicators. The findings indicate that although Curitiba imposes a similar or higher fare burden relative to user incomes, it offers significantly lower service value across various dimensions, including modal diversity and infrastructure quality. In contrast, Lisbon’s integrated governance model for bus and tram networks proves effective in enhancing accessibility and sustainability, despite some coordination issues with centrally governed transport networks. This study contributes to the international discourse on the limitations of single-modal transport systems and highlights the necessity of institutional integration, long-term investment, and adaptive governance frameworks for urban mobility transformation in the 21st century.

1. Introduction

1.1. Background to the Problem and Structure of the Article

The design, construction, implementation, and continuous improvement of efficient urban public transport systems constitute fundamental pillars for promoting sustainable, inclusive, and liveable cities. In contexts characterized by intense urban pressure, accelerating climate change, growing socioeconomic challenges, and rapidly evolving mobility demands, the way cities structure, finance, and operate their mobility modes directly affects multiple dimensions of urban life including quality of life, social equity, economic productivity, environmental sustainability, and public health outcomes.

Curitiba, the capital of Paraná state in southern Brazil, achieved international recognition as the pioneering city in the implementation of the Bus Rapid Transit (BRT) system during the 1970s and 1980s. Through innovative urban planning and integrated land-use transport planning, Curitiba became, throughout the 1980s and 1990s, a prominent international reference for integrated urban planning combined with efficient public transport provision. The city’s BRT model has been studied and replicated in over 200 cities across six continents, influencing urban transport policy globally.

Conversely, Lisbon, Portugal’s capital and largest city, has consolidated its position in recent decades as a case of a multimodal system undergoing expansion and modernization. The city’s transport network incorporates metro (underground), suburban trains, historic and modern trams, buses, and river ferries, all increasingly integrated through a unified fare system and collaborative governance structures. This integration is anchored in a semi-integrated metropolitan governance model that, while encompassing bus and tram networks comprehensively, still faces challenges in fully coordinating with centrally managed modes.

While Curitiba represents the emblematic model of the Global South based predominantly on high-capacity road-based transit, Lisbon emerges as a Global North experience that successfully combines modal diversity with substantial structural investments, many of which supported by European Union cohesion and structural funds. This fundamental duality, between a pioneering but potentially stagnating monomodal system and an evolving, investment-rich multimodal network, provides fertile ground for critical comparative analysis focused on cost-efficiency, accessibility, sustainability, and user satisfaction.

The article is structured in 7 sections following this introduction. In Section 2 we present the public transport theoretical framework from a social perspective, and key concepts related to BRT systems, multimodality, governance, path dependence, and cost-efficiency are reviewed. Section 3 presents the methodological approach, including data sources, analytical framework, and research limitations. Section 4 and Section 5 provide detailed analyses of the two case studies, from historical development to recent trends. Section 6 offers a systematic comparative analysis of the two cases. Section 7 discusses the results, with a focus on institutional, economic, and political contexts, and proposes some key issues for transport policy. Finally, Section 8 summarizes the main findings, presenting policy recommendations, and indicating future research.

1.2. The Curitiba Paradox

Despite the Curitiba model having been extensively replicated in developing countries, the system shows signs of stagnation in its structural development and technological advancement. The system that once represented cutting-edge innovation at the time has remained, in many aspects, largely unchanged in its fundamental structure and operational model, despite growing demand for public transport. Simultaneously, fare costs for users have maintained relatively high levels when measured as proportions of local average and minimum wage incomes, generating questions about the system’s continuing effectiveness as a public mobility policy instrument.

Analyses indicate that a typical low-income worker in Curitiba making two round trips daily spends approximately 35–40% of the minimum wage solely on public transport, a proportion that exceeds international benchmarks and raises equity concerns [1]. This high relative cost burden, combined with perceptions of declining service quality, deteriorating infrastructure, and limited technological innovation, has contributed to declining ridership and increasing automobile dependence among those who can afford alternatives [2].

1.3. Lisbon’s Transformation

In contrast, Lisbon has demonstrated progress in multiple dimensions of public transport provision. The city has advanced in modal integration, ticketing system simplification, service digitalization, and particularly in fare burden reduction after, the implementation of the Navegante metropolitan pass in 2019 and the national Tariff Reduction Support Plan (PART). These policy innovations have resulted in reductions in user costs (the monthly pass representing approximately 4.6% of the national minimum wage), increases in ridership (around 25%), and improved user satisfaction across demographic groups [3].

Furthermore, Lisbon has benefited from sustained investment in infrastructure modernization, fleet renewal, accessibility improvements, and technological advancement including real-time passenger information systems, mobile ticketing applications, and integrated journey planning tools. These investments, supported by European Union funds and Portuguese national government commitments, have allowed Lisbon, in a short space of time, to significantly improve the functioning and attractiveness of its transport system.

1.4. Research Hypothesis and Objectives

In light of this contrasting context, this paper conducts a detailed comparative study of the public transit systems in Curitiba and Lisbon, emphasizing the interplay between user costs, structural efficiency, and the value of services provided. The primary assertion of this research is that the disparities in modal structures, financing techniques, and governance models give rise to differences in user-oriented cost efficiency when we look at Curitiba and Lisbon.

To test this hypothesis, the analysis focuses on four interconnected dimensions: governance and institutional arrangements, network structure and spatial coverage, financing mechanisms and fare policies, and service quality. Through this multidimensional framework, the analysis evaluates cost-efficiency from the user perspective while also identifying transferable lessons, best practices, and policy implications relevant to other urban contexts facing similar mobility challenges.

By comparing Curitiba and Lisbon—two cities with contrasting yet instructive trajectories, one marked by relative stagnation following early innovation, and the other by sustained transformation supported by political commitment and investment—the analysis sheds light on how institutional, economic, and political contexts shape user outcomes and system performance. The cross-continental comparative approach enriches transport literature by bridging quite different perspectives, while the in-depth case study design allows insights and policy lessons relevant to cities confronting similar challenges related to modal stagnation, financing limitations, governance fragmentation, and accessibility problems.

2. Theoretical Framework

2.1. Public Transport as Public Policy and Social Infrastructure

Public transport networks constitute far more than mere physical infrastructure or service provision [4] because they are an essential public service, increasingly recognized as fundamental for exercising citizenship rights, accessing urban opportunities, and participating fully in economic and social life [5]. Beyond its immediate functional dimension of providing accessibility, public transport plays a role as a redistributive policy instrument with capacity to mitigate socioeconomic inequalities by enabling access to employment, education, healthcare, and cultural opportunities [1,6].

Contemporary literature emphasizes that efficient and sustainable public transport systems must balance and integrate three fundamental pillars: accessibility (both spatial coverage and economic affordability), sustainability (encompassing environmental impact and long-term financial viability), and quality (including comfort, safety, reliability, and user experience) [7,8]. These dimensions are interdependent and mutually reinforcing, requiring integrated governance structures, coherent policy frameworks, and consistent long-term investment sustained beyond political cycles.

The recognition of public transport as an essential social infrastructure, rather than merely a commercial service, shape financing models, governance structures, and performance evaluation frameworks [9]. This perspective justifies public subsidies, prioritizes accessibility and equity objectives alongside efficiency considerations, and demands democratic accountability and user participation in system planning and operation.

2.2. The BRT Model and Its Innovation, Diffusion, and Limitations

The Bus Rapid Transit model emerged in Curitiba during the early 1970s as an innovative response to urban mobility challenges in resource-constrained contexts where conventional metro systems appeared financially prohibitive [10]. The model’s characteristics include dedicated bus lanes physically separated from mixed traffic, pre-boarding fare collection enabling faster boarding and alighting, level boarding through elevated stations and specially designed vehicles, high-capacity articulated or bi-articulated buses, and integration with urban development through transit-oriented zoning policies [11].

The BRT concept gained international recognition for offering service characteristics approaching Light Rail Transit (LRT) quality, including high capacity, reliability, and speed, at capital and operational costs lower than rail-based systems. This cost advantage, combined with implementation flexibility and relatively short construction timelines, made BRT attractive for cities in developing countries facing severe mobility challenges with limited financial resources [12].

However, accumulated experience and research have identified structural limitations inherent to BRT systems, particularly those implemented without sustained investment and institutional support. Ref. [12] document that numerous BRT systems across Latin America and Asia suffer from operational saturation, inadequate maintenance, infrastructure deterioration, and limited integration with complementary transport modes. Ref. [13] argues that BRT success depends on continuous investment, strong institutional capacity, political commitment, and effective enforcement—factors frequently absent or inconsistent in developing country contexts.

Ref. [14] emphasizes that BRT, despite its advantages for medium-capacity corridors, cannot fully substitute for rail-based systems in very high-demand corridors where capacity requirements exceed practical bus system limits. Modal diversity and comprehensive network integration emerge as essential requirements for developing comprehensive, resilient, and adaptable urban mobility systems capable of serving diverse travel patterns and user needs [15].

On the other hand, we should also emphasize that BRTs consume more space than an LRT corridor, namely in stations where express buses can overtake the slowest ones.

2.3. Multimodality and System Integration

Multimodality refers to the coexistence and functional integration of different transport modes, including cycling and micro-mobility options, within a unified coordinated system. Contemporary transport literature emphasises that efficient and user-centred systems are those enabling seamless transitions between modes through integrated ticketing systems, coordinated schedules and service planning, adequate physical integration infrastructure (transfer stations, intermodal hubs), and unified information systems [16].

Ref. [17] argue that multimodal integration is crucial for maximizing network coverage, service flexibility, and system resilience. Different modes present distinct advantages: metro and trains excel in high-capacity corridors with concentrated demand; buses provide flexible, cost-effective coverage in medium-density areas; light rail and trams serve medium-capacity corridors while supporting urban development; ferries utilize waterways where available. Integrated multimodal networks leverage these complementary strengths, providing users with options suited to diverse trip purposes, distances, and preferences.

European cities, including Lisbon, Amsterdam, Copenhagen, and Zurich, exemplify this integrated multimodal approach, where metro, trains, light rail, trams, buses, and cycling infrastructure operate in coordinated form under unified or closely coordinated governance structures. Users benefit from seamless transfers, unified fare systems, coordinated scheduling, and integrated information.

However, achieving genuine multimodal integration presents challenges [18], particularly regarding: (1) institutional coordination across multiple operators and government levels, (2) sustained investment requirements for infrastructure and technology, (3) fare revenue allocation among operators, (4) service coordination and scheduling, and (5) political commitment sustained beyond electoral cycles. These challenges are particularly acute in developing country contexts characterized by institutional fragmentation, fiscal constraints, and political instability [19].

2.4. Governance, Institutions, and Path Dependence

Transport system governance, encompassing institutional structures, regulatory frameworks, decision-making processes, and accountability mechanisms, influences operational efficiency, service quality, investment patterns, and user outcomes. Ref.[20] emphasise that fragmented governance characterized by multiple uncoordinated actors, overlapping jurisdictions, and conflicting objectives tends to produce inefficient systems, suboptimal service quality, and poor user experiences.

The new institutionalism in political science [21] offers analytical frameworks for understanding how institutions (formal rules, informal norms, organizational structures, and established practices) shape public policies, constrain or enable change, and produce path-dependent trajectories. Path dependence concepts [22] prove particularly relevant for understanding why transport systems frequently resist transformation even when facing evident inefficiencies, changing demands, or technological opportunities.

Path dependence operates through multiple mechanisms: (1) sunk costs in existing infrastructure creating resistance to modal diversification, (2) established institutional structures and routines resisting reorganization, (3) political coalitions defending existing arrangements, (4) technical standards and operational practices becoming locked-in, and (5) user habits and expectations adapting to existing systems. These mechanisms explain why pioneering systems like Curitiba’s BRT, despite evident limitations, resist fundamental transformation toward multimodal integration.

In Curitiba’s case, ref. [2] demonstrates how institutional path dependence rooted in the BRT success contributed to subsequent system stagnation. The success that brought international recognition created institutional resistance to modal diversification, technological innovation, and governance reform. Established interests, including bus operators, municipal agencies, and urban planning professionals, defended the existing BRT-centred model against proposals for metro construction, light rail implementation, or metropolitan governance integration.

Conversely, Lisbon’s metropolitan governance model, despite inherent complexity and coordination challenges, has demonstrated capacity for adaptation, innovation, and sustained investment [23]. The metropolitan authority (Autoridade Metropolitana de Transportes and its operator, Transportes Metropolitanos de Lisboa—TML) coordinates bus and tram services across 18 municipalities, while maintaining relationships with centrally managed operators. This structure, though imperfect, has enabled implementation of transformative policies like the Navegante pass and sustained infrastructure investment programs.

2.5. Cost-Efficiency, Fare Policy, and Subsidy Economics

Cost-efficiency analysis in public transport contexts involves comparing service costs, including both operational costs and capital investments, with benefits delivered to users, cities, and society [24]. From the user perspective, the most directly relevant metric is the relationship between fares paid and service value received, measured through dimensions including network coverage, service frequency, travel time, comfort, reliability, safety, and accessibility.

However, comprehensive cost-efficiency analysis must also consider broader social benefits (positive externalities) generated by public transport, namely: (1) congestion reduction through automobile trip substitution, (2) air quality improvement and greenhouse gas emission reduction, (3) road safety improvements, (4) urban development and land value impacts, (5) social inclusion through mobility access, and (6) economic productivity through labour market accessibility [24]. These broader benefits justify public subsidies even when fare revenues fail to cover operational costs.

Fare policy represents a crucial instrument for ensuring accessibility, managing demand, influencing modal choice, and generating revenue. Contemporary fare policy debates increasingly emphasise accessibility and equity objectives, recognizing that high fares relative to incomes effectively exclude low-income populations from mobility opportunities and urban participation [25]. Progressive fare policies incorporate income-based discounts, comprehensive monthly passes, free or reduced fares for specific groups (students, elderly, unemployed), and integration across modes to minimize transfer penalties [7].

Subsidy levels and structures vary across countries and regions, reflecting different political priorities, fiscal capacities, and institutional traditions. European public transport systems generally receive public subsidies, typically covering 50–70% of operational costs, enabling relatively low fares and high service quality. In contrast, Latin American systems traditionally depend heavily on fare revenue, with subsidies covering only 10–30% of costs, implying higher fares and often compromising service quality and accessibility [12].

Recent trends, however, show increasing recognition, even in developing countries, that subsidies are both economically justified (by positive externalities) and socially needed (for accessibility and equity). Examples include Brazil’s Free Fare Movement advocacy, Colombia’s subsidized fare systems, and various fare reduction programs across Latin America. These policy shifts reflect growing understanding that public transport is an essential social infrastructure deserving public investment.

3. Methodology

3.1. Research Design and Epistemological Approach

This study adopts a predominantly qualitative research approach grounded in comparative case study methodology [26]. Case study research enables in-depth, contextualized investigation of contemporary phenomena within real-world settings, proving particularly valuable when boundaries between phenomenon and context are not clearly evident and when understanding requires attention to contextual complexity, historical trajectories, and institutional dynamics. The comparative approach facilitates systematic identification of similarities and differences between cases, enabling pattern recognition, hypothesis generation and testing, and theory development [27].

The selection of Curitiba and Lisbon as case studies was based on five criteria: (1) comparable population sizes and metropolitan complexity; (2) distinct yet instructive trajectories (pioneering innovation versus sustained transformation); (3) different institutional and economic contexts; (4) availability of data and documentation; and (5) potential for generating transferable lessons relevant to other cities facing similar challenges.

3.2. Sources and Indicators Used

Data collection combined multiple sources and methods, following established principles for case study research emphasizing triangulation and evidence convergence (

Table 1. Data collection strategy and sources.

Source Type	Main Content	Indicators/Information Extracted	Geographical Scope	Time Period
Official documents and institutional reports	Annual reports, strategic plans, public policy documents, concession contracts, regulatory frameworks	Governance structures, operational models, institutional arrangements, investment strategies	Curitiba and Lisbon	2015–2025
Statistical and operational data	Ridership statistics, network characteristics, fleet data, operational performance, financial records	Passenger volumes, network length, number of routes and vehicles, service frequencies, fares, costs, subsidy levels	Curitiba and Lisbon	2019–2025
Academic and technical literature	Peer-reviewed journal articles, doctoral dissertations, master’s theses, technical studies	Critical analyses, theoretical frameworks, comparative assessments, structural limitations and best practices	International, with focus on both case studies	2000–2025
International organizations and specialized institutions	Reports from the World Bank, UITP, ITDP and other international bodies	Standardized indicators, international benchmarks, policy recommendations	International	2010–2025
Recent news and media coverage	News articles, official announcements, interviews, expert commentary	Recent system changes, reforms, institutional conflicts, public perception	Curitiba and Lisbon	2024–2025
Web-based and digital sources	Operator and authority websites, user information portals, journey planning tools, social media platforms	Up-to-date operational information, digital services, user feedback and public discourse	Curitiba and Lisbon	2024–2025

).

3.3. Analytical Framework and Indicator Operationalization

The comparative analysis was structured around a framework that allows for a systematic comparison of the public transport systems in Curitiba and Lisbon, even though their socioeconomic and institutional backgrounds are quite different. This framework is based on the concept of user-oriented cost-efficiency, which is about the balance between the financial costs faced by users and the value of the structure and services provided by the transport system. Instead of just sticking to descriptive comparisons, the analysis uses operationalized indicators that are categorized into four analytical dimensions which are: governance structure, network configuration, financing mechanisms, and service quality. Each dimension includes specific variables that facilitate a structured comparison across the cases.

3.3.1. Operational Definition of Cost-Efficiency

The research presented here analyses cost-efficiency from the users’ perspective, rather than from the financial perspective of the operators. Instead of assessing technical efficiency through output ratios (such as cost per passenger-kilometre), the study examines how the financial burden felt by users relates to the structural and service characteristics made available to them. This approach is in line with academic consensus that public transport is a fundamental element of social infrastructure, where key indicators of policy success revolve around accessibility and affordability. Consequently, the study focuses on indicators of proportional accessibility and on the structural characteristics of the service that shape how users perceive the value of the system, rather than concentrating solely on measures of economic productivity at the operator levels.

The main measure of accessibility applied here is the Fare Cost Index (FBI = Monthly Transport Cost/Monthly Minimum Wage), where Monthly Transport Cost represents the estimated monthly expenditure for a user making two daily journeys and Monthly Minimum Wage corresponds to the official statutory minimum wage applicable in each case study.

3.3.2. Complementary Structural Indicators

To capture the multidimensional nature of service value, additional structural indicators were defined and applied across both case studies.

These include:

-

Modal Diversity Index (MDI)

The Modal Diversity Index represents the number of distinct public transport modes operating within the metropolitan system (MDI = Number of Available Transport Modes). Modes considered include:

i.

Metro;

ii.

Suburban rail;

iii.

Bus;

iv.

Tram/Light Rail;

v.

Ferry.

Higher values of MDI indicate increased system flexibility, redundancy, and coverage potential.

-

Rail Backbone Presence Indicator (RBPI)

This binary indicator captures whether the system includes a high-capacity grade-separated rail backbone: RBPI = 1 (presence of metro or equivalent rail infrastructure) or 0 (absence of rail-based backbone).

This variable reflects the structural capacity limitations commonly associated with exclusively bus-based systems and, in most cases, the higher operational speed and regularity of rail systems in segregated infrastructure.

-

Fare Integration Indicator (FII)

This indicator captures the presence of unified ticketing systems allowing multi-modal travel under a single fare structure: FII = 1 (Integrated metropolitan fare system) or 0 (Fragmented or partial integration).

Fare integration is widely recognized as a key determinant of system usability and accessibility, not only for its simplification for users, but also because it does not penalize any change of transport mode in a trip.

3.3.3. Service Quality Indicators

Service quality was assessed using a multi-method approach combining quantitative performance indicators and a structured qualitative evaluation. The main service variables included:

i.

Infrastructure condition (categorized as modernized, transitional, or deteriorated);

ii.

Availability of real-time passenger information systems;

iii.

Accessibility infrastructure implementation;

iv.

User satisfaction indicators (when available).

These indicators were extracted from different sources (government publications, organizational information, and feedback from users), allowing for a well-rounded evaluation of both perceived and actual service quality.

3.3.4. Integrated Comparative Indicator Framework

Table 2. Analytical framework and evaluation dimensions.

Analytical Dimension	Core Focus	Key Indicators/Variables	Type of Analysis
Governance and operational structures	Institutional organization and regulatory framework of public transport systems	Governance model, legal framework, regulatory authority, operator structure, contractual arrangements, metropolitan coordination, stakeholder participation	Qualitative, comparative
Network structure and modal coverage	Physical configuration and functional scope of the transport network	Modal diversity, network extension, service coverage, stop/station density, service frequency, operating hours, capacity and crowding levels	Quantitative and qualitative
Financing and fare policy	Economic structure and user cost burden	Revenue sources, subsidy levels, fare structure, pricing strategies, affordability (fare as % of income), discount schemes, financial sustainability	Quantitative, comparative
Service quality and user experience	Performance and perceived quality of transport services	Infrastructure condition, vehicle quality, technology adoption, accessibility, reliability, safety, punctuality, user satisfaction	Mixed-methods

summarizes the structured analytical framework applied across both case studies.

The appropriate use of continuous and categorical indicators ensures that comparisons are based on measurable characteristics as well as rather than solely, on qualitative descriptions.

3.3.5. Hypothesis Evaluation Strategy

The working hypothesis of this study proposes that differences in user-oriented cost-efficiency between Curitiba and Lisbon are associated with variations in modal diversity, fare integration, and financing structures, rather than being attributable to any single structural feature by itself. Instead of using rigorous statistical techniques, the hypothesis was analyzed via a structured cross-case comparison with standardized measures. The backing for the hypothesis was evaluated through:

i.

Comparison of Fare Burden Index values;

ii.

Comparison of Modal Diversity Index values;

iii.

Evaluation of Rail Backbone Presence;

iv.

Assessment of Fare Integration structures;

v.

Comparative analysis of service quality indicators.

The consistency of results across various indicators was interpreted as evidence supporting the hypothesis.

This methodological approach is consistent with the practices employed in comparative case studies within urban transport research, where structured evaluation based on indicators enables an analytical comparison between heterogeneous metropolitan contexts.

3.3.6. Limitations in Economic Efficiency Metrics

Traditional metrics for assessing operator-level efficiency, like cost per passenger-kilometre or operating expenses per vehicle-hour, were not consistently available in a comparable manner across the two case studies. Variations in accounting systems and organizational frameworks made it challenging to create directly comparable production efficiency metrics.

Thus, the study adopts a cost-efficiency framework that focuses on user perceptions, highlighting measures of proportional accessibility and indicators of service structure that can be compared across diverse institutional settings. This method facilitates analytical comparisons while recognizing the typical data availability challenges faced in international transport research.

3.4. Comparative Analysis Approach

The comparative analysis followed a sequential, multi-stage approach. The process progressed from systematic system characterization of each case to cross-case comparison across the four analytical dimensions, followed by explanatory interpretation of observed differences, integrated cost-efficiency assessment from the user perspective, and synthesis of policy implications. This structured approach ensured analytical consistency and transparency throughout the comparative process (Figure 1).

3.5. Cross-Case Normalization and Comparability

A major methodological challenge in international comparative studies on transport lies in effectively comparing systems that operate within distinct socio-economic, institutional and infrastructural contexts. Curitiba and Lisbon exhibit notable differences in aspects such as national income levels, fiscal resources, institutional structures and their historical trajectories in transport development. To address these disparities, this research opted for normalization across cases. Rather than focusing exclusively on absolute values, the comparative framework emphasizes relative, proportional and categorical metrics, facilitating meaningful assessments across diverse contexts. Three additional normalization techniques were implemented:

3.5.1. Income-Based Normalization

Transport affordability was standardized using proportional indicators expressed relative to income levels.

The primary metric applied was the Fare Burden Index (FBI), defined as FBI = Monthly Transport Cost/Monthly Minimum Wage.

By expressing transport costs as a proportion of the minimum wage, this method allows for a comparison of cities operating under different monetary systems and purchasing power conditions. The aim is thus to reduce the distortions that would arise from a direct comparison of nominal fares.

All monetary values were converted into comparable reference values where necessary, with the analysis giving priority to proportional indicators to ensure comparability between cases.

3.5.2. Structural Normalization

Differences in metropolitan scale and infrastructure development were addressed through the use of structural indicators, rather than purely quantitative measures of network size, such as the total number of kilometres of the network or the size of the fleet, incorporating categorical and presence-based indicators, including:

i.

Modal Diversity Index (number of available transport modes);

ii.

Rail Backbone Presence Indicator;

iii.

Fare Integration Indicator.

These structural indicators allow comparison of system architecture and functional capacity beyond of city size, enabling evaluation of qualitative differences in network configuration.

This approach recognizes that transport system performance depends not only on scale but also on structural organization and modal composition.

3.5.3. Institutional and Policy Context Normalization

The variations in institutions and governance between Curitiba and Lisbon were clearly taken into account while analyzing the results. Lisbon functions under a framework established by the European Union, which is known for significant public funding and ongoing support for infrastructure projects. In contrast, Curitiba exists within a Brazilian institutional framework that has traditionally depended more on farebox revenue and faces limitations in public funding availability.

To address these contextual variations, institutional factors were looked at comparatively instead of through a normative lens. Policy tools like subsidy frameworks or fare integration initiatives were assessed in relation to their national and regional contexts rather than against one universal benchmark. This context-aware approach lessens the chance of mistakenly linking performance disparities exclusively to system design, recognizing the impact of wider political and economic settings.

3.5.4. Temporal Alignment of Data

To improve comparability across datasets, the study prioritized data from overlapping time periods whenever possible. The primary analytical reference period corresponds to 2024–2025, supplemented by historical data used exclusively for contextual interpretation. Where earlier data were used, temporal differences were explicitly acknowledged to avoid misleading comparisons.

This temporal alignment ensures that comparisons reflect contemporary system conditions rather than historical asymmetries.

3.5.5. Limitations of Cross-Case Comparability

Despite efforts to standardize the data, it was not possible to achieve full equivalence between the case studies due to inherent contextual differences.

Consequently, the conclusions drawn from this exercise should be interpreted as analytical comparisons rather than statistically generalizable results. The aim of the analysis is not to establish universal classifications, but to identify structured differences in user-oriented cost-effectiveness across contrasting institutional and infrastructural settings.

3.5.6. Controlling for Macroeconomic Context Differences

A key methodological consideration in this comparative study concerns the impact of macroeconomic and fiscal differences between the two urban contexts. Lisbon benefits from consistent support from national and European funding sources, whilst Curitiba has traditionally relied more heavily on approaches based on ticket revenue. To address this discrepancy, the assessment does not prioritize an analysis of the system’s absolute efficiency or capital funding levels. Instead, the research analyses relative outcomes for users, using proportional indicators such as the Fare Burden Index (FBI) and various structural categories. Consequently, the aim of the comparison is not merely to link performance differences to the choice of transport modes (such as BRT versus rail), but rather to explore how the interaction between modal structure, funding models and governance capacity affects accessibility for users and service characteristics in different institutional contexts.

3.6. Distinction Between Empirical and Prospective Evidence

This study uses both real operational data and future policy insights from approved transport programs. It separates current system performance from expected future changes. The empirical data focuses on operational datasets, historical stats, and user surveys for 2024–2025, covering usage, fares, subsidies, and satisfaction. Future elements include approved infrastructure projects, concession changes, and tech initiatives that are not fully in place yet, impacting the system’s future rather than current performance.

This separation ensures the analysis is based on actual data while recognizing ongoing institutional and infrastructure changes.

4. Case Study A—Curitiba

4.1. Historical Context and System Development

The development of Curitiba’s public transport system is intrinsically linked to the city’s urban planning, representing one of the most celebrated examples of integration between land use and transport planning in the developing world. During the 1960s and 1970s, under the leadership of urban planners at the Institute for Research and Urban Planning of Curitiba (IPPUC), the city implemented an innovative urban development model [28]. This model integrated land-use planning, transport infrastructure, and urban design, establishing high-density zoning along designated transport corridors [14]. BRT system, inaugurated in 1974 with the first exclusive bus lane along the North–South structural axis, became the centrepiece of this integrated model [1]. Its innovations included bus lanes physically separated from general traffic, tube-shaped stations allowing level boarding and off-board fare payment, high-capacity articulated buses, and coordinated feeder networks connecting peripheral neighbourhoods to structural axes [14].

Throughout the 1980s and 1990s, the system gained international recognition, positioning Curitiba as a reference for urban planners and transport experts worldwide. The BRT concept developed was subsequently replicated and adapted in over 200 cities across six continents, including large systems like TransMilenio in Bogotá and Metrobús in Mexico City [12]. However, starting around 2000, observers began to note signs of systemic stagnation [28]. Despite population growth, no new structural BRT axis was built after 1995 [2]. The reliance on a single mode (buses) presents capacity constraints, infrastructure deterioration, and a sustained decline in ridership [29]. This crisis was exacerbated by the COVID-19 pandemic, which resulted in a 63% drop in user volume at its peak [30], with the system experiencing a slow recovery that stabilized at around 710,600 passengers transported on weekdays in 2025 [31] (Figure 2).

Recognizing the limits of this institutional path dependence, Curitiba initiated a phase of “transitional modernization” in the 2020s. Driven by the Curitiba Climate Change Adaptation and Mitigation Plan (PlanClima) approved in 2020, the city pursued an agenda of decarbonization and network upgrading [32]. Instead of pursuing a heavy and financially prohibitive subway system, which had paralyzed local planning for decades, the public administration began testing high-capacity intermediate hybrid technologies [33].

In late 2025, the operational introduction of the Digital Rail Transit (DRT) occurred on a metropolitan corridor between the municipalities of Pinhais and Piraquara [34]. Manufactured by CRRC, this 30-m-long bidirectional electric vehicle, which operates on rubber tires, is guided by high-precision magnetic sensors embedded in the asphalt. This technology bridges the gap between a traditional BRT and a LRT system without the costs associated with installing railway infrastructure. This shift demonstrates a strategic pivot away from strict monomodality toward a diversified, technology-driven metropolitan network.

4.2. Governance and Institutional Structure

Historically, Curitiba’s public transport system was managed and regulated by URBS (Urbanização de Curitiba S.A.), a mixed-capital company controlled by the municipal government, operating in conjunction with IPPUC, which dictates urban and spatial planning guidelines [35]. The URBS model was based on concession contracts that relied on remuneration tied to the volume of transported passengers, a “net cost” paradigm that incentivized bus overcrowding and restricted private operators’ investments in service quality [36]. However, to address accumulated inefficiencies, Curitiba’s governance structure is undergoing a reform, driven by a new concession modelling process led by the Brazilian Development Bank (BNDES) with implementation scheduled for 2025/2026 [33] (

Table 3. Principal institutional actors in Curitiba’s public transport system.

Institution	Governance Level	Main Responsibilities	Role in System Integration
URBS (Urbanização de Curitiba S.A.)	Municipal (Mixed-Capital Company)	Management, tactical planning, oversight, and tariff regulation of the capital’s fleet and infrastructure.	Operational control of the RIT (Integrated Transport Network) within the municipality and management of the ticketing system.
IPPUC (Institute for Research and Urban Planning)	Municipal (Autarchy)	Long-term strategic planning, land use-transport integration, and development of structuring projects (e.g., Novo Inter 2).	Alignment of transport with urban zoning and decarbonization goals (PlanClima).
AMEP (Paraná Metropolitan Affairs Agency)	State/Metropolitan (Autarchy)	Coordination of metropolitan transport across 29 municipalities, development of the PDUI-RMC, and management of state subsidies.	Facilitation of physical and tariff integration across municipal borders; fund transfers.
BNDES (Brazilian Development Bank)	Federal (Financial Institution)	Technical-financial structuring of the new transport concession, risk modeling, and contract auditing.	Guaranteeing economic viability for the transition to electric (Zero Emission) fleets.
Private Operating Consortia	Private (Concessionaires)	Fleet operation, vehicle maintenance, and workforce hiring.	Direct execution of the service under quality metrics (SLA) required by the new contract.

).

The new concession structured by BNDES introduces a modern governance framework. The 15-year contracts, distributed across five operational lots with an estimated cost of R$1.1 billion (approximately €192 million), alter the system’s economic incentives [37]. The remuneration model transitions from a “per passenger” basis to a “gross cost” model based on the kilometers driven [36]. This shift transfers demand risk from private operators to a newly established Public Guarantee Fund, ensuring financial stability for long-term investments in new fleets [38]. Furthermore, the governance framework incorporates performance metrics, tying up to 3% of operators’ remuneration directly to service quality and operational efficiency indicators [36].

Simultaneously, metropolitan governance is undergoing formal institutionalization. The State of Paraná has elevated its supramunicipal governance capacity through the creation and empowerment of AMEP [19]. Tasked with the formulation of the Integrated Urban Development Plan of the Curitiba Metropolitan Region (PDUI-RMC), AMEP acts as a coordinating body for the 29 municipalities adjacent to the capital, establishing unified mobility guidelines [39]. AMEP now manages subsidy transfers, including an annual allocation of R$60 million (€10.5 million) directly to URBS and R$216 million (€37.7 million) to the broader metropolitan network, intended to maintain physical integration between municipalities and offset operational deficits [39].

4.3. Network Structure and Modal Coverage

The architecture of Curitiba’s transport network is founded on a hierarchical Trunk-Feeder system, utilizing dedicated structural corridors to form the backbone of the Integrated Transport Network (RIT) [14]. The contemporary system comprises 333 bus lines, 329 tube stations, and 21 integration terminals, operated by a fleet of 1543 vehicles covering over 217,000 km every weekday [31]. Historically, this network was criticized for its monomodality, relying exclusively on buses that faced capacity constraints on high-demand axes, resulting in declining commercial speeds and user experience [29].

To respond to this structural exhaustion, the network is undergoing its largest physical expansion in three decades, financed by multilateral development banks [40].

Aiming to break the limitations of the traditional BRT model, Curitiba is executing works focused on increasing commercial speed and infrastructure resilience (

Table 4. Major infrastructure projects in Curitiba (2024–2026).

Project Name	Financing Agency	Investment	Length (km)	Main Technological and Physical Upgrades
Novo Inter 2 Program	Inter-American Development Bank (IDB)	US$106.7 million	38 km	Implementation of Solar Prism Stations (energy-autonomous, climate-controlled), concrete road requalification, and traffic light priority.
East–West BRT	New Development Bank (NDB)	US$75 million	20 km	Reconstruction of intermodal terminals (e.g., Capão da Imbuia), 30% increase in service capacity, 23-min reduction in travel time.
Digital Rail Transit (DRT)	Government of the State of Paraná (AMEP)	R$6 million (Pilot Phase)	10 km	100% electric 30 m vehicle, guided by virtual magnetic sensors, capacity for 280 passengers, operating on the Pinhais–Piraquara metropolitan connection.

).

Supported by a $106.7 million (€95 million) loan from the Inter-American Development Bank (IDB), the “Novo Inter 2” project is requalifying 38 km of routes that transport approximately 181,000 passengers daily across 28 neighbourhoods [38]. This project introduces the “Solar Prism” station model, which replaces older tube stations with photovoltaic glass infrastructure that is thermally comfortable, climate-resilient, and equipped with universal accessibility and real-time digital connectivity [41]. In parallel, the New Development Bank (NDB) is financing the $75 million (€66.8 million) modernization of the “East–West BRT” axis, which includes rebuilding integration centres and is designed to increase flow capacity by 30%. The infrastructure improvements are calculated to reduce travel times on the East-West axis by up to 23 min [38].

Furthermore, modal diversification is being pursued to bypass the constraints of rubber-tired transit. The introduction of the Digital Rail Transit (DRT) pilot in the metropolitan network marks the region’s first operational foray into integrating rail-emulating technologies [34]. By operating a 30-m, 280-passenger bidirectional vehicle guided by virtual magnetic tracks, the network achieves the capacity metrics of an LRT system without the disruption and costs associated with deploying steel tracks.

4.4. Financing and Fare Policy

The political economy of transport financing in Curitiba is historically characterized by a dependence on farebox revenues, which traditionally covered up to 85% of the system’s operational costs [36]. This financial architecture generated a cyclical crisis: increasingly higher fares to maintain operational viability, which, in turn, alienated middle-class passengers and imposed a financial burden on low-income populations [1].

Recognizing that fare affordability is a cornerstone of public transport’s utility as social infrastructure, a lesson demonstrated by the subsidized Navegante pass in Lisbon [3], Curitiba implemented intervention mechanisms to shield users from operational cost inflation. For the transition period of the new concession between 2025 and 2026, the municipal and state governments froze the user fare at R$6.00 (approximately €1.05) [42]. To maintain this freeze, direct public subsidies were increased. The new BNDES concession modelling incorporates an estimated R$800 million (€140 million) in structural public subsidies to bridge the gap between the technical fare required for operations and the social fare paid by the public [37]. This financial burden is now structurally shared with the State of Paraná through AMEP, bringing Curitiba’s financing structure closer to a model that treats mobility as a subsidized social good [24] (Figure 3).

Beyond freezing the base fare, Curitiba modernized its pricing strategy through the introduction of the Time-based Single Ticket (Digital Temporal Integration). This system allows users to make unlimited transfers between different lines and modes within a designated time window without paying a second fare [36]. While Curitiba does not yet offer a universal flat-rate monthly metropolitan pass identical to Lisbon’s Navegante, the introduction of temporal integration—combined with targeted social policies, such as half-fares on Sundays and free passes for registered unemployed individuals—acts as an economic equalizer [42]. State and municipal data indicate that external temporal integration generates direct savings for passengers traveling between Curitiba and metropolitan cities [34].

4.5. Service Quality and User Experience

Service quality and user experience in Curitiba have experienced a measured recovery after years of deterioration. According to the 2025 QualiÔnibus survey, conducted in partnership with the World Resources Institute (WRI Brasil), which evaluated a stratified sample of 958 users, overall system satisfaction registered an increase of +0.5 points compared to 2024 results [36]. The system achieved scores of 7.5 out of 10 for Customer Service, 7.3 for Network Integration, and 7.2 for Universal Accessibility [36]. The availability of passenger information and digital tools scored 7.0, reflecting the deployment of Mobility as a Service (MaaS) infrastructure, including official applications like Meu Estar Digital and the Curitiba App, and the use of digital payments [43].

Despite these advances, structural challenges persist. The QualiÔnibus data identifies static infrastructure and urban externalities as primary detractors. Comfort at bus stops reached 5.6 points, validating the necessity of the IDB-financed implementation of the Solar Prism stations to replace older infrastructure that suffers from inadequate thermal control [41]. Public safety in and around the transit environment registered 4.9, the system’s lowest metric, highlighting broader urban challenges beyond URBS’s operational control [36].

A finding from the 2025 survey is the public support for decarbonization: 82% of transport users support the accelerated transition to electric buses [44]. Respondents correlated Zero Emission vehicles with the mitigation of engine noise and localized air pollution [36].

4.6. Current Challenges and Approved Future Developments

Curitiba’s public transport system is at a critical inflection point. Rather than facing a trajectory of inevitable decline, institutional spheres have orchestrated a strategic pivot to address its structural vulnerabilities. The current public policy objective is to execute a technological, green, and governance transition while ensuring viability. Curitiba’s long-term prospects are anchored in four fundamental pillars:

i.

Fleet Decarbonization. In alignment with the 2020 PlanClima, Curitiba has initiated a transition to electromobility budgeted at over R$1.5 billion (€262 million) [38]. The new concession mandates the introduction of 245 zero-emission electric buses in the first five years of operation [3]. The system is legally bound to achieve a 33% zero-emission fleet by 2030, culminating in the 100% eradication of operational fossil fuels by 2050 [33].

ii.

Modal Diversification. The planning dogma that confined Curitiba to rubber-on-asphalt monomodality has been challenged. The State Government’s commitment to pilot the Digital Rail Transit (DRT) technology demonstrates a pragmatic approach [34]. By adopting vehicles guided by virtual magnetic tracks (capable of transporting up to 280 passengers) the system aims to achieve capacity and comfort comparable to a Light Rail Transit (LRT) system, avoiding the costs associated with underground subway projects.

iii.

Metropolitan Governance. The challenge of municipal fragmentation is being addressed through the maturation of the Integrated Urban Development Plan (PDUI-RMC) led by AMEP, which provides legal foundations for master plans in the region [39]. Ensuring legislative continuity for the annual state subsidy package (currently R$216 million/€37.7 million) is crucial to guarantee borderless fare and route integration among 29 municipalities.

iv.

Financial Engineering. The city has bundled transport into the broader “PRO Curitiba” public works program, totalling R$6 billion (€1.05 billion) in planned municipal investments through 2028 [45]. To protect this transformation, the city must maintain fiscal governance to service active credit lines of over US$180 million from the IDB and NDB. Simultaneously, the BNDES’s gross cost remuneration model will require ongoing auditing to ensure the transfer of revenue risk does not overwhelm municipal solvency [45].

5. Case Study B—Lisbon

5.1. Historical Context and System Development

Lisbon’s public transport history extends over 150 years. The tram system, inaugurated in 1873 as a horse-drawn tram and electrified in 1901, represents one of Europe’s oldest urban transport networks. The metro system, inaugurated in December 1959, was the first in the Portuguese-speaking world [46].

After the democratic revolution in 1974 and Portugal’s integration into the European Economic Community (now European Union) in 1986, the transport system underwent a transformation. EU membership provided access to structural and cohesion funds targeting infrastructure development. These funds enabled investments in transport infrastructure that would have been financially challenging through Portuguese national resources alone.

During the 1990s and 2000s, Lisbon experienced a phase of expansion and modernization of its public transport system. The metro network expanded from its original two-line configuration to a four-line system. The 1998 Lisbon World Exhibition (Expo 98) drove this process, triggering infrastructure projects including the development of the Oriente multimodal hub and the extension of metro services to eastern areas of the city and the airport.

In parallel, suburban rail services operated by the national rail company (Comboios de Portugal—CP) were modernized, with electrification, station upgrades, rolling stock renewal, and service frequency improvements. Since the new century, a private company (Fertagus) operates a train service linking the south bank to Lisbon, and a light rail system (MTS) operates in two municipalities on the south bank. Surface transport also underwent reorganization, as bus and tram networks were progressively restructured to complement metro services.

These investments were accompanied by the development of intermodal transfer facilities designed to facilitate seamless transfers between metro, rail, bus, and river transport. More recently, the 2019 implementation of the Navegante monthly metropolitan pass represented a shift in fare policy. This unified pass, valid across all modes and all 18 municipalities in the metropolitan area, simplified ticketing and reduced costs for users. The policy was enabled by the national Tariff Reduction Support Plan (PART), through which the central government and municipalities compensate operators for revenues lost due to fare reductions [3].

5.2. Governance and Institutional Structure

Lisbon’s governance structure reflects the complexity inherent in managing a multimodal metropolitan system encompassing multiple operators, technologies, and jurisdictional scales (

Table 5. Principal institutional actors in Lisbon’s public transport system.

Institution	Governance Level	Mode(s) Managed	Core Responsibilities	Role in System Integration
Metropolitano de Lisboa, E.P.E.	National (state-owned)	Metro	Planning, construction, operation, and maintenance of the metro system	High-capacity backbone; key urban integration nodes
Carris—Companhia de Carris de Ferro de Lisboa, S.A.	Municipal (Lisbon City Council)	Buses, LRT and trams	Operation of surface transport within Lisbon municipality	Urban coverage and feeder services
CP—Comboios de Portugal, E.P.E.	National (state-owned)	Suburban and regional trains	Operation of suburban rail services and national rail network	Metropolitan and regional connectivity
Transtejo/Soflusa	National (state-owned)	Ferries	Operation of river crossings across the Tagus	Cross-river metropolitan integration
TML—Transportes Metropolitanos de Lisboa	Metropolitan	Buses and trams (metropolitan coordination)	Planning, contracting, and coordination of surface transport across 18 municipalities	Fare integration and network coordination
AML—Área Metropolitana de Lisboa	Metropolitan	Strategic (all modes)	Strategic planning, policy coordination, management of Navegante system	Metropolitan-scale governance
Transportes Coletivos do Barreiro	Municipal	Buses	Operation of surface transport within Barreiro municipality	Urban coverage and feeder services
MobiCascais	Municipal	Buses	Operation of surface transport within Cascais municipality	Urban coverage and feeder services
Fertagus	Private company (government public concession)	Suburban train	Train connexions between south and north bank of metropolitan Lisbon	Cross-river metropolitan integration
Metro Transportes do Sul—MTS	Private company (government public concession)	LRT in the municipalities of Almada and Seixal	Operation and maintenance of the LRT network	Urban coverage and feeder services

).

This multi-layered structure reflects an institutional evolution attempting to balance operator autonomy with metropolitan coordination. The structure is not without challenges, particularly regarding coordination between bus/tram networks (managed by TML) and rail and ferry networks (managed by central government entities). However, this governance model has enabled advances in integration, service quality, and user-centred policies. The Navegante pass exemplifies successful coordination despite institutional fragmentation, requiring complex negotiations among multiple operators with different cost structures and institutional cultures. The central government’s commitment through PART funding was essential for overcoming operator resistance.

5.3. Network Structure and Modal Coverage

Lisbon’s public transport system exemplifies multimodality through the integration of several transport modes operating at different spatial scales. These modes are designed to be complementary, with each serving distinct demand profiles and spatial functions (

Table 6. Modal structure of Lisbon’s public transport system.

Mode	Network Scale	Key Characteristics	Primary Function	Integration Features
Metro	4 lines, 45 km, 56 stations	High-capacity, high-frequency, fully grade-separated	Backbone for high-demand urban corridors	Interchanges with trains, buses, ferries; unified fare system
Suburban trains	4 main lines, 100+ stations	Electrified, regional reach, higher speeds	Metropolitan and regional connectivity	Integrated fares; major multimodal hubs
Buses	140+ routes (Lisbon)	Flexible routing, surface operation	Area coverage and feeder services	Coordinated with rail; integrated ticketing
Trams	5 routes	Medium-capacity, heritage and modern rolling stock	Urban corridors and tourist flows	Integrated fares; shared stops with buses
Ferries	4 river crossings	High-capacity river transport	Cross-river metropolitan links	Direct connection to metro and rail

).

Lisbon’s modal diversity generates structural advantages by allowing transport capacity to match different demand profiles. High-capacity metro services serve the city’s highest-demand corridors; suburban trains accommodate longer-distance metropolitan trips; buses and trams provide flexible coverage in medium and lower density areas. This combination enables a degree of geographic coverage and service adaptability that would be unattainable within a single-mode system.

These advantages are reinforced by intermodal integration. Major multimodal stations, such as Oriente, Entrecampos, Sete Rios, Cais do Sodré, and Marquês de Pombal, facilitate connections between metro, rail, bus, and ferry services through coordinated layouts, schedules, and travel information. Fare integration through the Navegante pass reduces barriers to multimodal travel, allowing unlimited use of all modes for a single monthly fee. In parallel, integrated information systems and journey planning applications support multimodal travel by providing users with real-time network-wide information.

5.4. Financing and Fare Policy

Lisbon’s transport system receives public subsidies, reflecting European policies and Portuguese political commitment to public transport accessibility. According to operator financial reports and TML data, approximately 50–60% of operational costs are covered by public funding from municipalities and central government, with the remainder from fare revenues and other minor sources (advertising, commercial activities).

The structure of monthly passes reflects the simplicity and affordability of the fare system (

Table 7. Navegante monthly pass structure in the Lisbon Metropolitan Area.

Pass Type	Monthly Price (€)	Eligibility	Geographical Coverage	Modes Included
Navegante Metropolitano	40	Standard adult users	All 18 metropolitan municipalities	Metro, trains, buses, trams, ferries
Navegante Municipal	30	Users travelling within a single municipality	One municipality (e.g., Lisbon)	Metro, buses, trams (and local services)
Navegante 4/18	20	Children and youth aged 4 to 18	All metropolitan municipalities	All modes
Navegante +65	20	Seniors aged 65 and over	All metropolitan municipalities	All modes
Navegante Social	Free	Registered low-income individuals	All metropolitan municipalities	All modes

). Rather than relying on complex zonal pricing, the system offers a limited number of differentiated pass types based on user profile and spatial coverage.

Portugal’s national minimum wage in 2025 is €870 per month (gross). The Navegante Metropolitano pass at €40 represents approximately 4.6% of the minimum wage. For a minimum wage worker, the monthly transport cost is fixed, predictable, and affordable, regardless of trip frequency or distance within the metropolitan area (Figure 4).

The Tariff Reduction Support Plan (PART) enabled this policy, through which the national government (75% in the first years) and municipalities (25%) compensate transport authorities for revenues lost due to fare reductions compared to previous higher fares. PART represents a financial commitment, approximately €100 million annually, justified by policy objectives including social inclusion, environmental sustainability, congestion reduction, and economic productivity.

Recent data confirms this policy’s success because ridership increased approximately 25–30% in the first year following Navegante implementation, with particularly strong growth among previously underserved populations. User satisfaction surveys show improvements, with the pass consistently rated as one of the most popular public policies in recent Portuguese history. In December 2025, authorities confirmed that Navegante prices would not increase in 2026, maintaining affordability despite rising operational costs [47].

5.5. Service Quality and User Experience

Lisbon’s public transport system exemplifies effective service due to investments in infrastructure, technology, and user-focused policies. Rail modes, especially the metro, are characterized by reliability, modernity, and accessibility, enhancing user experience with minimal wait times. However, recent metro line construction has led to some service disruptions, including delays and frequency reductions. Surface transport modes like buses and light rail enhance urban connectivity, with ongoing improvements in fleet quality and environmental performance. Historic trams serve both transport and cultural functions, despite accessibility limitations. Digital initiatives, including real-time information and electronic ticketing, enhance travel convenience and multimodal integration. Accessibility considerations are increasingly prioritized in metro infrastructure, while retrofitting programs address gaps in older facilities. Safety is generally high, though peak crowding and occasional service interruptions pose challenges. User satisfaction surveys reveal favourable opinions on Lisbon’s transport, notably post-Navegante fare system implementation, although overcrowding and surface service irregularities are common concerns.

5.6. Recent Developments and Future Prospects

Lisbon’s public transport system continues to evolve through a combination of infrastructure expansion, technological innovation, and policy-driven integration. Ongoing investments in metro and LRT expansions constitute a central pillar of this strategy, with new lines improving connectivity to underserved areas and strengthening links between urban and suburban zones. These projects reinforce the role of rail-based transport as the structural backbone of the metropolitan network.

At the same time, resources are being directed toward fleet renewal and decarbonization across surface modes. The progressive replacement of diesel buses with electric and liquefied gas vehicles, alongside investments in energy efficiency for rail operations, aligns Lisbon’s transport policy with broader national and European climate objectives.

Digitalization represents another key axis of ongoing modernization. The gradual integration of Mobility as a Service (MaaS) platform, expanded real-time information systems, and unified digital interfaces is reshaping how users interact with the transport system. These initiatives reinforce multimodal travel and enhance the usability of the network.

Efforts to strengthen metropolitan integration are also continuing, particularly in relation to coordination between metropolitan surface transport managed by TML and centrally governed rail services. While institutional fragmentation remains a challenge, incremental improvements in information sharing, scheduling coordination, and physical integration at transfer points signal a gradual movement toward more cohesive metropolitan governance. Parallel investments in accessibility upgrades aim to close remaining gaps.

5.7. Demand Growth and Capacity Pressure Following Fare Reform

The Navegante travel card, launched in 2019, has increased demand for public transport in Lisbon by around 25–30 per cent, improving access but also putting pressure on transport offer. The increase in demand has led to greater congestion during peak hours, particularly on the busiest metro and suburban rail routes, with passenger numbers exceeding comfort levels, and sometimes not be able to enter in vehicles. Capacity management measures have been adopted, but new vehicles and infrastructure improvements typically take much longer than changes to fare policy. As passenger numbers grow, this causes greater wear and tear on vehicles and facilities, consequently increasing future maintenance costs. This situation highlights the need to align fare reforms with system capacity and maintenance investments. Rapid growth in demand can affect service reliability, compromising punctuality and passenger boarding times, particularly during peak periods. These same challenges have been observed in other metropolitan systems following fare reductions, highlighting the operational hurdles associated with increased demand. In summary, whilst fare reductions improve access and passenger numbers, they bring with them capacity management dilemmas that require careful analysis and investment. Through its experience, Lisbon highlights both sides of the coin: the advantages and the operational issues tied to substantial affordability efforts.

6. Comparative Analysis

6.1. Governance and Institutional Capacity

Curitiba is evolving from a historically fragmented, purely municipal model into a multi-tiered governance framework. The establishment of AMEP and the execution of the PDUI-RMC provide a nascent metropolitan coordination mechanism. The strategic partnership with BNDES to restructure concessions from a net-cost to a gross-cost model improves investment security and operator accountability. While still reliant on state-municipal subsidy pacts rather than unified central funding like EU cohesion funds, this new architecture mitigates the institutional path dependence that previously stalled innovation [2].

Lisbon presents a more complex governance structure with multiple entities managing different modes at different scales. This complexity creates coordination challenges. However, TML provides metropolitan-scale governance for surface modes, enabling coordinated planning and fare integration. Modal specialization allows different entities to specialize in their respective modes, potentially enabling greater technical expertise. Access to EU funds, national subsidies, and metropolitan resources provides financial backing for investments. Lisbon’s governance, despite greater complexity, demonstrates superior capacity for metropolitan coordination, modal integration, and sustained long-term investment. The metropolitan scale of TML, combined with EU financial support and national government commitment, enables transformative policies (Navegante) and sustained infrastructure investment. However, coordination between TML-managed surface modes and centrally managed rail networks remains imperfect, with different institutional cultures and priorities sometimes creating friction.

6.2. Network Structure and Modal Diversity

While fundamentally anchored in its legacy BRT architecture, Curitiba is actively breaking its strict monomodality to address capacity constraints. The investment for the Novo Inter 2 and BRT Leste-Oeste projects transforms aging corridors into higher-efficiency infrastructure (e.g., Prisma Solar stations). The introduction of the Digital Rail Transit (DRT) pilot demonstrates a pragmatic pivot towards high-capacity, light-rail-equivalent technology, optimizing intermediate technologies for a Global South financial reality.

Lisbon’s genuinely multimodal network (comprising metro, trains, trams, buses, and ferries) provides advantages. Through capacity matching, different modes serve corridors with appropriate capacity, utilizing the metro for the highest demand, trains for suburban connections, and buses for broader coverage. This diversity ensures flexibility and resilience, as multiple modes provide alternatives and redundancy. The combined network achieves comprehensive coverage that would be impossible with any single mode. Lisbon’s modal diversity represents a competitive advantage, enabling superior capacity, flexibility, coverage, and user experience compared to Curitiba’s monomodal system. This difference is not merely quantitative but qualitative; multimodal systems respond to different users’ needs. The contrast is particularly stark on high-demand corridors. Curitiba’s structural BRT axes, despite dedicated infrastructure, face capacity constraints and cannot provide the speed, reliability, or comfort of Lisbon’s metro on comparable corridors.

6.3. Financing and Fare Policy

The contrast between Curitiba and Lisbon is stark in relation to financing structures and fare policy. Curitiba’s public transport system remains heavily dependent on fare revenues, which account for approximately 80–85% of operational costs, with limited public subsidy support. This financing model constrains policy flexibility and creates a self-reinforcing cycle. High fares are required to cover operating costs, imposing a disproportionate burden on low-income users, restricting accessibility. In turn, elevated fares combined with declining service quality encourage users with viable alternatives to shift toward private modes, reducing ridership and further increasing per-passenger costs. This downward spiral limits resources for maintenance and modernization.

In a departure from its historical reliance on farebox revenues, Curitiba froze user tariffs at R$6.00 (approximately €1.05) through 2026. This is sustained by state and municipal subsidies, estimated at R$800 million (€140 million) under the new BNDES concession structure [37] supplemented by R$216 million (€37.7 million) in state integration funds via AMEP [39]. Furthermore, the implementation of “Temporal Integration” digital ticket functions as an economic equalizer. While Lisbon’s pass remains cheaper as a proportion of the minimum wage, Curitiba’s shift toward subsidizing transport as an essential social infrastructure represents a closure of the conceptual gap between the two fiscal paradigms.

Lisbon’s approach reflects an understanding of public transport as essential social infrastructure deserving public investment, justified as a social instrument with externalities. The Navegante pass exemplifies how transformative policy innovation, enabled by political commitment and adequate financing, can simultaneously improve accessibility and increase ridership, creating virtuous rather than vicious cycles.

6.4. Service Quality and User Experience

Differences in service quality reflect distinct investment capacities. While Lisbon leverages sustained EU investments for a consistently high-quality experience, Curitiba’s 2025 WRI QualiÔnibus survey reveals measurable user satisfaction improvements (+0.5 overall increase) [36]. Strong performance in digital information and temporal integration mitigates legacy infrastructure complaints. While urban security remains a vulnerability (scoring 4.9), the system is poised for a qualitative leap. The BNDES-mandated rollout of 245 electric buses and the IDB-funded Prisma Solar stations directly answer the 82% user mandate for decarbonisation [44] replacing the narrative of systemic deterioration with one of digital and environmental modernization.

Lisbon delivers higher service quality across most dimensions. Rail-based modes, especially the metro, provide a reliable and high-frequency backbone. Surface modes extend coverage and offer flexibility, while ongoing fleet renewal and electrification programs enhance comfort and environmental performance. Digital tools reduce uncertainty and facilitate seamless multimodal travel. These qualitative differences are reflected in user perceptions. Survey data indicate consistently higher satisfaction levels in Lisbon.

6.5. Integrated Cost-Efficiency Assessment

The integrated cost-efficiency evaluation pulls together insights from the standardized indicators laid out in Section 3.3 and neatly summarized in Table 7. This assessment zeroes in on how user financial strain relates to the structural traits of each transportation system. By using the Fare Burden Index (FBI) as the main measure of affordability, the analysis shows that the projected monthly transport expenses in relation to minimum wage vary significantly between the two cities/regions. In Curitiba, the FBI sits at around 0.37 (37%), while in Lisbon, it is about 0.046 (4.6%). This clear inequality underscores a more intense economic pressure faced by low-wage earners in Curitiba in contrast to those residing in Lisbon. The Modal Diversity Index (MDI) demonstrates that Lisbon features a transportation structure consisting of several complementary modes, while Curitiba primarily relies on bus transit, even though there are active initiatives aimed at diversification. The Rail Backbone Presence Indicator (RBPI) points out that Lisbon has grade-separated rail infrastructure, whereas Curitiba currently lacks similar high-capacity rail setups, depending instead on bus trunk corridors. The Fare Integration Indicator (FII) uncovers differences in how ticketing is organized. Lisbon features a unified metropolitan fare system that allows for multimodal transfers with one monthly pass. In contrast, Curitiba has set up time-based integration mechanisms that allow for multiple transfers within specific time frames, which represents a middle ground in terms of fare integration. Financial structure indicators also add to the comparative analysis. Public financial support differs between the two systems, with Lisbon obtaining a more substantial amount of operational funding sourced from public revenues. Recently, Curitiba has amplified its subsidy amounts through newly developed concession frameworks and state assistance systems, signaling a transition towards more significant public financial participation. Elements linked to service quality, like user satisfaction indices and infrastructure enhancement projects, suggest that both systems are advancing, although at uneven rates. Lisbon takes advantage of its long-standing rail network and persistent modernization efforts, while Curitiba is energetically seeking policy modifications to upgrade its infrastructure, electrify its transport vehicles, and increase transportation variety. When you look at the combined picture of affordability, structural, financial, and service indicators, it becomes clear that the two systems yield different cost-efficiency results in the current context. Such variations not only illustrate technical features but also incorporate larger institutional, financial, and historical narratives. Instead of depicting a fixed performance scale, the comparative insights reveal how system arrangement, subsidy frameworks, and modal variety affect the link between user expenses and service provision. Therefore, the analysis backs up the idea that multimodal and integrated systems tend to have lower relative user cost burdens in the situations examined in this study.

Table 8. User-Oriented Cost-Efficiency and Structural Context Indicators.

Category	Indicator	Acronym	Focus	Curitiba	Lisbon
Core Efficiency Indicators	Fare Burden Index	FBI	User cost ratio	0.37	0.046
Core Efficiency Indicators	Public Subsidy Share	PSS	Financing ratio	~15%	~50–60%
Core Efficiency Indicators	Monthly Transport Cost	MTC	User expenditure	€92	€40
Structural Context Indicators	Modal Diversity Index	MDI	Structural descriptor	1	5
Structural Context Indicators	Rail Backbone Presence	RBPI	Structural descriptor	0	1
Structural Context Indicators	Fare Integration Indicator	FII	Institutional descriptor	0.5	1
Service Indicators	User Satisfaction Level	USL	Outcome indicator	38%	72%

standardized comparative cost-efficiency indicators based on operational definitions introduced in Section 3.3 and data sources documented in Appendix A. All affordability metrics are calculated using proportional indicators to enable cross-case comparability between Curitiba and Lisbon.

Curitiba’s cost-to-income ratio improves with new subsidies and investments. Lisbon benefits from established rail systems and EU financial support. The modifications in Curitiba hint at a shift, but their triumph is tied to effective implementation.

7. Discussion

7.1. Explaining the Differences: Contextual Factors

A wide range of structural, economic, institutional and historical factors shape the transport systems in Curitiba and Lisbon. These differences clearly reflect their unique national and metropolitan contexts, rather than merely technical choices.

Financial capacity and investment frameworks are key factors. Lisbon benefits from a wide range of funding options, including both national and EU financial support, which promotes sustainable infrastructure improvements. Curitiba, on the other hand, relies more heavily on local funding, with limited external resources, which impacts the development of its infrastructure. This reflects a quite different public policy regarding public transport systems. In one case, the major investment is considered a public obligation in order to guarantee a equitable and affordable accessibility to all. In the other case, the option is a tariff structure based in the principle of “pay as you go”, and consequently the provision of transport (and accessibility) is easily transferable to private operators, and consequently the fare should, as far as possible, cover the costs of the transport system.

Economic conditions also determine accessibility and subsidies. Portugal’s higher income supports fare systems based on subsidies, whilst Brazil has traditionally relied on fare revenue, although Curitiba is shifting towards public subsidies. These financial models demonstrate how national economies affect the accessibility of local transport.

Institutional development also influences the differences between the systems. Curitiba’s early adoption of Bus Rapid Transit (BRT) created a robust system that prioritized buses and built up significant expertise. In contrast, Lisbon has developed a multimodal system over time, integrating various transport services under unified governance. These historical developments shape current systems and growth trajectories.

Governance structures affect metropolitan coordination. Lisbon’s transport operates under a multi-layered governance model, promoting (despite its limitations) coordination between modes, whilst Curitiba has primarily followed a municipal governance approach, although reforms are encouraging greater metropolitan coordination. These changes indicate a continuous evolution of governance in both cities.

Transport outcomes are not influenced solely by design decisions, as broader factors, such as economic frameworks and funding trends, have a considerable impact on the situation. The study highlights how technical attributes interact with the institutional context, rather than indicating clear links between transport modes and their outcomes.

This contextual perspective enriches our understanding of cost-efficiency disparities arising from a combination of technical, institutional and economic influences, facilitating a more refined analysis of international transport networks.

7.2. Analytical Implications for Urban Transport Policy

The findings from the standardized indicators offer insights for metropolitan public transport design and management. These insights are observational, not prescriptive recommendations from the case study comparisons.

i.

Modal Diversity and Network Resilience. More modal diversity boosts structural flexibility and redundancy. The passenger demand in Lisbon is effectively met by multiple transport methods. Single-mode systems may struggle with capacity as demand rises. This shows that diverse modes enhance network resilience in cities.

ii.

Integration as a Determinant of System Usability. Fare integration and network design impact user access and usability. Unified fare systems simplify transactions and encourage multimodal travel. Both case studies link transfer integration to better system coherence. This showcases the significance of cooperative coordination among institutions in relation to user experience.

iii.

The Role of Public Subsidies in Affordability Outcomes. Subsidy levels affect the link between operational costs and user fares. Systems with more public funding impose lower costs on users, according to the Fare Burden Index. On the other hand, systems relying more on fares may lead to higher user costs. This highlights how financing affects user accessibility. However, as discussed in Section 5.7, rapid demand increases associated with fare reductions may generate short-term operational pressures, including peak congestion and maintenance demands, requiring coordinated capacity planning.

iv.

Long-Term Investment Cycles and Infrastructure. Performance Infrastructure quality is tied to consistent investment cycles. Systems with steady funding show better infrastructure upgrades and technology use. Breaks in financial backing can bring about old infrastructure and service-related challenges. This indicates that ongoing investment is crucial for operational success.

v.

Metropolitan Governance and Institutional Coordination. The way institutions are set up affects service coordination across boundaries. The administration of governance within metropolitan areas supports the integration of transport routes, fare regulations, and planning initiatives between local councils. Shifts in governance promote better alignment, showcasing that institutional changes are necessary for the evolution of transport.

vi.

Technology Adoption and Service Efficiency. Tech innovations like digital systems and updated fleets enhance service reliability and user info access. Both cases show a shift towards digital transport management systems. This indicates that adopting technology is increasingly important for public transport performance.

vii.

Accessibility and Universal Design Considerations. Improvements in accessibility and universal design enhance inclusivity for various demographic groups. Evidence shows that systems that prioritize accessibility in planning are more usable. The significance of ensuring accessibility in public transport planning is highlighted by these outcomes.

viii.

Institutional Path Dependence and System Evolution. The analysis shows how past investments and institutional setups affect future development paths. When transportation networks concentrate on just one type, they risk stagnation; however, those that embrace multiple types show greater flexibility. This bolsters arguments that accentuate the vital nature of path dependence in infrastructure advancement.

Overall, these insights emphasize the need for integrated planning that considers design, institutional frameworks, and financial sustainability together. The evidence highlights the importance of developing strategies that reflect local circumstances instead of applying standard policies everywhere.

7.3. International and Intergovernmental Support as Enabling Factors

The findings show that external and intergovernmental support is key for metropolitan transport systems’ development. The Lisbon example shows how multi-level governance aids infrastructure growth and integration. This city benefits from access to national and supranational funding sources for infrastructure projects like metro expansions and intermodal facilities. These funds help maintain a steady investment cycle, minimizing disruptions in modernization efforts.

The framework of multi-tiered governance enhances collaborative learning and regulatory harmony. Being part of larger networks allows for the exchange of technical standards and planning practices, enhancing coordination among transport operators.

The case of Lisbon also illustrates that policies aimed at stimulating demand, whilst effective in improving accessibility, can create operational pressures linked to overcrowding and infrastructure utilization, which highlights the need for coordinated investment planning.

In a different approach, Curitiba depends on regional finance, state synergy, and global banking for its advancement. The latest initiatives backed by international monetary organizations showcase how collaborations from outside can foster growth and innovation when domestic resources fall short.

This comparison indicates that structured funding and collaborative frameworks affect how quickly and extensively transport systems evolve. However, it does not suggest that specific models are easily transferable, as successful development often depends on stable funding and tailored governance to local conditions.

Such insights point out the vital need for institutional resilience and financial steadiness to secure enduring transport successes. Global partnerships represent merely one component within a comprehensive network of technical, financial, and governance aspects that determine transport effectiveness.

8. Conclusions

This research compares the public transport systems of Curitiba and Lisbon, focusing on user cost-efficiency through specific indicators. It looks at affordability, structure, institutions, and service quality to highlight differences in these two cities’ transport systems: The Fare Burden Index shows significant differences in user expenses between Curitiba and Lisbon, with Curitiba having a higher percentage of minimum wage spent on transport. This finding underscores how financing and subsidies affect affordability. Structural indicators reveal that Lisbon’s system is multimodal with rail infrastructure, whereas Curitiba relies mainly on buses, though it is moving towards more diverse tech. These structural aspects impact capacity and infrastructure growth. Financial indicators show that higher public funding in Lisbon correlates with lower user costs, while Curitiba’s reliance on fare revenue leads to higher user expenses. Recent changes in Curitiba suggest a shift towards better public funding involvement in transport. Service quality indicators show both systems are evolving but at different rates. Lisbon reflects long-term investments, while Curitiba is focused on modernization. Continuous investment is crucial for maintaining system effectiveness.

Finally, findings from the assessment suggest that using multiple transport methods often reduces user expenses, yet it is vital to analyze these insights within the particular economic and institutional frameworks of individual cities.

The comparative results enhance theories on path dependence, governance, and transport financing, showing how Curitiba’s infrastructure history affects its development and how Lisbon’s coordinated expansion supports adaptability.

Some limitations need to be recognized. To start, the analysis is based on data collected from institutional and administrative sources that differ in format and reporting standards. Even though normalization processes were implemented, we cannot ensure complete equivalence among datasets. Since the comparative strategy depends on a handful of case studies, it limits our scope for statistical extrapolation. Hence, the outcomes should be understood as having analytical relevance rather than broad applicability.

Further exploration might widen the analytical lens by featuring an increased number of case studies across distinct geographic regions and financial backgrounds. Investigating the recurring phases of infrastructure financing and subsidy influences may clarify the link between institutional advancement and the operational efficiency of transportation systems. Furthermore, blending environmental performance indicators and metrics of spatial accessibility could provide a deeper insight into cost-efficiency that goes past mere user affordability assessments.

In summary, the study indicates that user-focused cost-efficiency in metropolitan transport systems arises from the interplay of financial structures, network layout, governance abilities, and long-term investment trends. The comparative framework created in this research offers an analytical foundation for exploring these relationships and adds to ongoing conversations about the design and development of sustainable urban mobility systems.