Building Trust in Sustainable Journeys: The Interplay Between Green Marketing, Green Brand Trust, and Tourism Purchase Intentions

Abstract

This study aimed to examine the impact of green marketing on green purchase intention among tourists, with a specific focus on the mediating roles of brand engagement and green brand trust. The research sought to develop an explanatory model that integrates both cognitive and emotional dimensions in shaping sustainable tourism behavior. A quantitative approach was adopted using Partial Least Squares Structural Equation Modeling (PLS-SEM). Data were collected via a structured questionnaire distributed to tourists. A total of 882 valid questionnaires were analyzed in the study. The results revealed a significant and positive direct effect of green marketing on tourists’ green purchase intention. Additionally, green marketing had a significant positive influence on both brand engagement and green brand trust. Both mediators also had direct effects on green purchase intention and were found to play partial mediating roles in the relationship between green marketing and purchase intention. The study offers a dual theoretical contribution by integrating the Theory of Planned Behavior (TPB) and Attachment Theory to explain how green marketing influences eco-conscious purchasing decisions. Practically, it guides tourism organizations toward developing sustainability-focused marketing strategies that build trust and foster emotional engagement with green brands—ultimately encouraging more responsible consumer behavior and deeper tourist commitment to environmentally responsible offerings.

1. Introduction

The global tourism and hospitality industry is undergoing a paradigm shift, with environmental sustainability becoming a strategic imperative rather than a peripheral concern [1]. Tourists are increasingly seeking experiences that align with their environmental values rather than focusing only on service quality or price [2]. In this evolving context, green marketing has emerged as a central mechanism through which tourism organizations seek to communicate their commitment to ecological responsibility, reduce environmental harm, and simultaneously enhance their market position [3]. Unlike traditional promotion, it integrates sustainability into brand identity, influencing product design, service delivery, and stakeholder engagement [4].

As green marketing gains momentum, its implications extend beyond awareness generation [5]. It plays a decisive role in shaping consumer perceptions and building trust in tourism brands [6]. The authenticity of green marketing strongly influences brand engagement, reflecting tourists’ cognitive, emotional, and behavioral investment [7]. In highly competitive and experience-driven sectors such as tourism, brand engagement is not just desirable—it is essential for fostering customer loyalty, advocacy, and long-term brand relationships [8]. Engaged consumers often develop positive associations, participate in sustainability initiatives, and share their experiences within their social networks [9,10].

Moreover, the effectiveness of green marketing is deeply intertwined with the development of green brand trust—the degree to which consumers believe that a brand’s environmental claims are sincere, credible, and supported by actual practices [4,11]. Trust is especially critical in green tourism contexts, where the risk of “greenwashing”—false or exaggerated environmental claims—remains a persistent concern [12]. For green marketing to succeed, tourists must believe not only in the brand’s environmental promises but also in its capacity and willingness to deliver on them consistently [6,13]. Green brand trust reduces perceived risk and enhances confidence in eco-friendly purchasing decisions [14].

Given the increasing importance of sustainability in consumer decision-making, several key constructs have emerged as critical predictors of green purchase intention in the tourism sector [6]. At the forefront is green marketing, which functions as a foundational stimulus for environmentally driven consumer behavior [15]. By using eco-labels, energy-saving practices, certifications, and transparent communication, businesses shape tourists’ perceptions of responsibility [16]. These marketing efforts can positively influence tourists’ attitudes by aligning brand values with personal ecological concerns, thereby increasing the likelihood that tourists will choose environmentally responsible services [17]. Thus, green marketing serves as a direct antecedent to green purchase intention by establishing relevance and credibility around sustainability themes [18].

In addition to direct marketing, brand engagement has gained attention as a pathway toward sustainable consumer actions [19]. It encompasses emotional attachment, cognitive involvement, and active participation with a brand [20]. When tourists feel intellectually and emotionally connected to a tourism brand—particularly one that reflects their environmental values—they are more inclined to act in ways that support that brand, including the decision to purchase its green offerings [4,21]. Therefore, brand engagement is not merely an outcome of marketing communication, but a driving force that strengthens consumers’ internal motivation to favor green products and services [22].

Equally important is green brand trust, which reflects belief in the authenticity and reliability of a brand’s claims [23]. In tourism, where outcomes are intangible, trust becomes central to decision-making [24]. High levels of trust reduce uncertainty and reinforce confidence in eco-friendly services [25]. When brands consistently deliver on sustainability promises, tourists are more likely to intend green purchases [26].

This research is theoretically anchored in the Theory of Planned Behavior (TPB) and Attachment Theory. The TPB explains how tourists’ attitudes, perceived behavioral control, and social norms influence their intention to engage in environmentally responsible behaviors, providing a basis for linking green marketing efforts to green purchase intention [27]. At the same time, Attachment Theory highlights the emotional and psychological bonds that tourists form with brands, offering a lens to understand how brand engagement and green brand trust operate as critical mediators in the decision-making process [4,28,29]. Together, these theories create a robust framework that underpins the study’s conceptual model and strengthens the explanation of the relationships among the variables.

Although the integration of green marketing into the tourism and hospitality sector has gained increasing scholarly and managerial attention (e.g., [3,6,19]), there remains a notable gap in understanding how such marketing efforts translate into tangible consumer behavior—specifically, green purchase intention. Much of the existing literature tends to adopt a surface-level perspective, examining green marketing as an isolated promotional tool or exploring its influence on general consumer attitudes without fully investigating the psychological processes that mediate its effect (e.g., [30,31]). In tourism, where products are intangible and trust-intensive, emotional engagement and credibility are central, yet seldom examined together in structured models.

Furthermore, while brand engagement and green brand trust have each received attention in separate research streams, their interrelated mediating roles within a green marketing framework remain underexplored. Most prior studies (e.g., [14,32]) examined either emotional connection or credibility perceptions, without integrating both to explain consumer choice. This oversight has left a theoretical void in fully understanding the consumer decision-making process in response to sustainability-driven branding strategies. There is also a geographic and contextual bias in the literature, with a heavy concentration of studies in retail or manufacturing sectors, rather than service-oriented domains like tourism where personal experience, perception of authenticity, and brand values carry amplified importance.

In response to these limitations, the present study aims to construct a comprehensive and empirically testable model that captures the multidimensional influence of green marketing on tourists’ green purchase intentions. Specifically, it seeks to (1) examine the effect of green marketing on green purchase intention, brand engagement, and green brand trust, (2) assess the effect of brand engagement and green brand trust on green purchase intention, and (3) explore how they mediate these relationships. This provides a nuanced view of how sustainability messaging drives meaningful consumer action, contributing to academic discourse and offering practical insights for marketers.

2. Literature Review and Hypothesis Development

2.1. Theory of Planned Behavior—TPB and Attachment Theory

The Theory of Planned Behavior (TPB) offers a powerful lens through which to understand how tourists form intentions to engage in green purchasing behaviors [33]. It posits that intention is shaped by three primary factors: attitudes toward the behavior, subjective norms, and perceived behavioral control [34]. Within the context of sustainable tourism, TPB helps explain how tourists evaluate environmentally friendly services and decide whether or not to choose them [33]. Green marketing shapes attitudes through ecological, health, and social messages, and reinforces norms by portraying green behavior as socially accepted [35,36]. Moreover, when green marketing effectively communicates the accessibility and practicality of eco-friendly options, it enhances perceived behavioral control, thereby strengthening the likelihood of green purchase intention [37]. However, while TPB excels at explaining the cognitive and social precursors of intention, it does not fully account for the emotional dimensions of consumer-brand relationships, which are often central in tourism decision-making [27,38].

To address this limitation, attachment theory offers a complementary perspective that delves into the affective bonds consumers form with brands [28]. Originally developed in developmental psychology and later extended to marketing, this theory explains how individuals develop deep emotional attachments to brands that they perceive as trustworthy, value-aligned, and emotionally rewarding [29]. In the realm of green tourism, this attachment is often cultivated through consistent and meaningful brand interactions that resonate with a consumer’s environmental values and identity [39]. Authentic green marketing strategies foster emotional engagement, leading to stronger attachment and sustained brand preference [4]. This attachment manifests through increased brand engagement and heightened green brand trust, both of which function as mediating mechanisms that reinforce green purchase intention [40].

Together, TPB and Attachment Theory provide a comprehensive understanding of how green marketing shapes sustainable behavior. TPB explains the rational and social basis of intention, while Attachment Theory highlights emotional and relational pathways [4,27]. Integrating both frameworks enables a nuanced analysis of how tourists process messages, develop trust and engagement, and form intentions to act sustainably [41]. This dual-theoretical approach is particularly relevant in tourism, where decisions are shaped by both rational considerations and emotional identity [42,43].

2.2. The Effect of Green Marketing on Green Purchase Intention

Green marketing has moved beyond a promotional tool into a strategic orientation that reflects an organization’s environmental commitment and sustainability values [44]. In tourism, where consumers are guided by ethical considerations and value-driven choices, green marketing signals more than corporate responsibility—it communicates brand purpose, differentiation, and authenticity [4,45]. Unlike conventional marketing, which appeals mainly to functional benefits, green marketing engages with consumers’ broader value systems, invoking moral, emotional, and societal dimensions that align with pro-environmental identity and lifestyle [45,46]. Because tourism experiences are intangible and trust is paramount, the credibility and relevance of green marketing messages directly shape tourists’ evaluations and motivations [27]. When these messages are perceived as genuine, consistent, and aligned with ecological beliefs, they become internalized motivators for action [47,48]. The persuasive power of green marketing lies in its ability to build a coherent narrative that encourages tourists not only to consider but also to commit to environmentally responsible purchases [44]. Green marketing significantly enhances purchase intention by shaping environmentally conscious decision-making [6]. Similar results were reported by [49,50], who confirmed that intensified efforts strengthen green purchase intention. As well, ref. [51] showed that green initiatives contribute meaningfully to purchase intention. In addition, refs. [18,52] highlighted the role of clarity and credibility in marketing communications, while ref. [53] demonstrated this effect in eco-oriented branding campaigns. Further, ref. [54] confirmed the robustness of the relationship across consumer segments. So, the following hypothesis is developed:

H1. 

Green marketing has a positive effect on green purchase intention.

2.3. The Effect of Green Marketing on Brand Engagement

In sustainable tourism, green marketing acts not only as a channel for information but also as a catalyst for deeper consumer–brand interaction [55]. When tourism brands adopt green marketing, they communicate more than environmental credentials; they invite consumers into a shared narrative of ecological responsibility and long-term impact [56]. When conveyed authentically, this narrative encourages tourists to move from passive reception to active involvement [57]. Through this process, green marketing fosters psychological investment and alignment between brand purpose and individual values [4]. Brand engagement—comprising cognitive processing, emotional attachment, and behavioral participation—is especially influenced by how brands position themselves on social and environmental issues [58]. In tourism, where experiences are co-created and highly symbolic, strategies emphasizing transparency, ethical practices, and sustainability motivate tourists to interact with, support, and advocate for the brand [55,56]. As [59] showed, green marketing fosters stronger brand attachment by resonating with environmental values. According to [60], the role of transparent, sustainability-oriented communication in reinforcing consumer–brand connections. As well, ref. [19] confirmed that adopting green practices significantly enhances engagement by positioning the brand as socially and environmentally responsible. Hence, the following hypothesis is developed:

H2. 

Green marketing has a positive effect on brand engagement.

2.4. The Effect of Brand Engagement on Green Purchase Intention

Brand engagement is a multidimensional connection that extends beyond satisfaction or transactional loyalty to include cognitive attention, emotional resonance, and behavioral participation [61]. When tourists process sustainability messages, feel pride or belonging, and actively share or endorse brand experiences, they are more likely to support the brand through purchasing behavior [62]. Engagement thus serves as a conduit that transforms sustainability messages into behavioral intention [63]. Deeply engaged tourists do not view green purchasing as a single choice but as a natural extension of their relationship with the brand. Choosing eco-friendly products reinforces self-identity and moral consistency [33,64]. Engagement also enhances trust, reduces uncertainty, and strengthens commitment, which are critical for converting favorable attitudes into behavioral intentions in tourism [65,66]. According to [67], consistent and credible green marketing strengthens consumers’ psychological connection, especially when aligned with personal values. Likewise, Ref. [14] showed that environmentally focused initiatives deepen engagement and foster identification with socially responsible brands. Further, [63] confirmed that green marketing reinforces brand image and intensifies consumer commitment. Moreover, ref. [68] revealed that green efforts foster emotional engagement by building trust and credibility. Similarly, ref. [69] demonstrated that authentic, value-driven marketing amplifies engagement through shared sustainability beliefs. Therefore, the following hypothesis is developed:

H3. 

Brand engagement has a positive effect on green purchase intention.

2.5. The Mediating Role of Brand Engagement

Green marketing may directly influence tourists’ intention to purchase environmentally responsible services, but its impact often unfolds through deeper psychological mechanisms—most notably, brand engagement [6,70]. When green marketing is perceived as authentic, consistent, and value-driven, it encourages tourists to build meaningful connections with the brand. These connections go beyond simple exposure to green messages, cultivating shared values and emotional relevance that draw tourists into an ongoing relationship [44,71]. Through this process, tourists begin to engage with the brand not just as consumers but as participants in a larger environmental narrative [72]. Brand engagement thus mediates the persuasive appeal of green marketing, converting it into actionable behavioral intention [73,74]. Rather than acting in a linear manner, the effect of green marketing is filtered through the tourist’s psychological investment [41]. When engagement is strong, tourists are more likely to internalize sustainability messages, align them with personal identity, and act by choosing green offerings [75,76]. In this way, brand engagement amplifies the influence of green marketing by embedding it within a relational framework—turning information into emotional commitment and commitment into intention [44,77]. Accordingly, the hypothesis is developed:

H4. 

Brand engagement mediates the relationship between green marketing and green purchase intention.

2.6. The Effect of Green Marketing on Green Brand Trust

In tourism, where consumers cannot directly observe or verify a company’s environmental practices, green marketing becomes a primary mechanism for shaping credibility [78]. Demonstrations of ecological responsibility—such as highlighting sustainable operations, showcasing certifications, or communicating long-term goals—help reduce informational asymmetry and create reliability [44]. As tourists grow more selective, their trust depends on the consistency between promises and delivery [2]. When green marketing is perceived as authentic and transparent, it reassures consumers that environmental commitments are genuine and actionable [79]. Green marketing enhances brand trust by signaling ethical responsibility and consistent sustainability messaging [80]. As ref. [81] mentioned, consumers develop stronger trust when marketing efforts are transparent and environmentally aligned. Similarly, ref. [6] confirmed that green marketing builds trust by reinforcing perceived authenticity. In this vein, refs. [82,83] reported that green marketing contributes significantly to brand trust when sustained and aligned with ecological expectations. As ref. [84] highlights, effective green marketing strengthens trust by enhancing the brand’s reputation for environmental reliability. Therefore, the following hypothesis is developed:

H5. 

Green marketing has a positive effect on green brand trust.

2.7. The Effect of Green Brand Trust on Green Purchase Intention

In uncertain decision-making environments such as tourism, where services are intangible and environmental impact is hard to verify, trust becomes a decisive factor in shaping consumer behavior [62]. Green brand trust reflects the belief that a tourism brand both communicates sincere environmental values and consistently acts on them with integrity [23]. When tourists perceive genuine commitment rather than superficial green claims, this perception creates psychological safety, reduces risk, and strengthens confidence in the brand’s offerings [2,62,85]. Consumers who trust a brand’s environmental performance are more willing to support it through purchase decisions [82]. Trust in green attributes significantly boosts intention to buy eco-friendly products [86]. Moreover, ref. [87] emphasized that green brand trust reduces perceived risk and encourages sustainable choices. As well, ref. [88] reported that trust in a brand’s responsibility positively influences green purchasing behavior. Similarly, refs. [89,90] found that brand trust strengthens motivation to prefer sustainable products. More recently, ref. [23] confirmed that green brand trust remains a key determinant of eco-conscious purchasing intentions. Based on this understanding, the following hypothesis is developed:

H6. 

Green brand trust has a positive effect on green purchase intention.

2.8. The Meditating Role Green Brand Trust

Green marketing shapes tourists’ perceptions of a brand’s environmental responsibility, but perception alone does not always lead to action [91]. Whether this perception develops into behavioral intention depends on the level of trust consumers place in the brand’s environmental claims [92]. Green brand trust acts as a key intermediary, allowing customers to interpret marketing messages not as rhetoric but as credible commitments grounded in consistent practice [44]. When green marketing is viewed as authentic and value-driven, it fosters trust that the brand’s environmental messaging reflects genuine actions. This trust reduces uncertainty, reinforces belief in sustainability values, and provides moral assurance that consumers are making responsible choices [6,93]. In tourism—where environmental impacts are often intangible or delayed—trust is particularly important in guiding purchase decisions. Rather than relying only on persuasive appeals, tourists use trust to justify their intention to support green brands [27,33,94]. Thus, green brand trust becomes the pathway through which green marketing exerts its influence, mediating the relationship between marketing communication and the intention to purchase sustainable tourism products. Hence, the following hypothesis is developed:

H7. 

Green brand trust mediates the relationship between green marketing and green purchase intention.

To visually summarize the hypothesized relationships, the proposed research model is presented in Figure 1 at the end of this section.

3. Methods

3.1. Sample and Data Collection

The target population for this study consisted of tourists. Given the study’s focus on examining green marketing effects on individual perceptions and behavioral intentions, tourists were selected as the most appropriate unit of analysis. A structured, self-administered questionnaire was designed based on established measurement scales from the literature. To ensure contextual relevance and access to informed respondents, a purposive non-probability sampling technique was employed, as it allowed the deliberate targeting of tourists with direct exposure to green marketing in tourism settings. Data collection focused on both domestic and international tourists. A hybrid distribution strategy was used, combining physical dissemination at partner tourism service points with digital distribution via official online platforms, maximizing reach, participation diversity, and ecological validity. Over the course of the data collection period, which extended from January 2025 to the end of June 2025, a total of 1471 questionnaires were distributed. Of these, 882 valid responses were retrieved and included in the final dataset, yielding a response rate of approximately 59.9%, which is considered satisfactory for field-based research in tourism and service-oriented environments.

Participants were informed in advance about the academic nature of the study and assured that their participation was entirely voluntary. Ethical considerations were rigorously upheld; respondents were guaranteed full anonymity, and all data were treated with strict confidentiality, with no identifying personal information collected or disclosed. Prior to the main data collection phase, the questionnaire was pilot-tested on a subset of the target group to ensure conceptual clarity, linguistic precision, and cultural appropriateness. Minor adjustments were incorporated based on the pilot feedback to enhance instrument reliability and contextual alignment.

3.2. Measures

The study employed a set of established and validated measurement instruments; each tailored to the tourism context to ensure conceptual alignment and respondent clarity. All constructs were measured using multi-item scales derived from previous scholarly work. Responses were recorded on a five-point Likert scale, allowing for the consistent quantification of attitudes, perceptions, and intentions. Green marketing was assessed using three items adapted from the work of [95,96]. A sample item illustrating this construct stated: “This agency/company seems to be environmentally responsible,”. To measure brand engagement, the study applied four items developed by [97]. One such item included: “I feel good when I use this brand,”. Green brand trust was measured using five items adapted from [98]. For instance, the item “I feel that the green product or brand’s environmental reputation is reliable”. Green purchase intention was assessed using five items adopted from [99]. An example statement is: “I choose to buy products that are environment friendly”. Lastly, the questionnaire included three demographic variables—namely, gender, age, and education level.

3.3. Common Method Bias

To enhance the robustness and credibility of the statistical inferences, the study assessed the potential presence of common method variance (CMV)—a methodological concern that may arise when both independent and dependent variables are measured using self-reported data from a single source at a single point in time. CMV can artificially inflate or deflate observed relationships among constructs, particularly in cross-sectional survey designs, leading to biased parameter estimates and misleading conclusions [100]. In order to evaluate the extent to which CMV might affect the results, this study employed Harman’s single-factor test, a widely used diagnostic procedure recommended by [101]. Using principal component analysis (PCA) with all measured items entered simultaneously and no rotation applied, the goal was to determine whether a single latent factor would emerge and account for the majority of the variance. If one factor were to explain more than 50% of the total variance, this would suggest a serious concern regarding method bias. The analysis revealed that the first unrotated factor accounted for less than 50% of the total variance, confirming the absence of a dominant single factor. This indicates that no substantial portion of the covariance among the variables can be attributed to the measurement method alone. Therefore, common method bias does not pose a significant threat to the validity of the study’s findings, and the observed relationships among constructs can be interpreted with greater confidence. To further mitigate any residual concerns, respondents were assured of anonymity and confidentiality during data collection, and the questionnaire items were carefully structured to reduce evaluation apprehension and response consistency artifacts.

3.4. Data Analysis

The analytical framework of this study was based on Partial Least Squares Structural Equation Modeling (PLS-SEM). This methodological choice was guided by both the nature of the research model and the objectives of the study. PLS-SEM, as a variance-based approach, was selected because the study emphasizes prediction-oriented analysis and the exploration of complex causal relationships, rather than strict theory confirmation. These features closely match the aim of this study, which seeks not only to test established relationships but also to explore new mechanisms linking green marketing, brand engagement, green brand trust, and purchase intention. Although the relatively large sample size (n = 882) would also allow for the use of covariance-based SEM (CB-SEM), PLS-SEM was preferred for several reasons. First, CB-SEM focuses primarily on model fit and theory validation, whereas this study is concerned with prediction and theory development in a relatively underexplored context. Second, PLS-SEM provides greater flexibility in handling complex models with multiple mediating effects, which is a central aspect of the proposed framework. Third, PLS-SEM is more robust in cases of non-normal data distributions and multicollinearity, conditions that are common in behavioral and attitudinal survey data. Beyond these strengths, PLS-SEM allows for a comprehensive assessment of both the measurement model (validity and reliability of constructs) and the structural model (testing direct, indirect, and mediating effects), offering methodological rigor aligned with the multidimensional nature of sustainable tourism constructs [2,102]. In this regard, the choice of PLS-SEM strengthens the methodological rigor of the study, as it is well-recognized in the literature as a powerful tool for both small and large samples when prediction, theory extension, and complex model testing are central goals [103]. This makes PLS-SEM particularly appropriate for advancing understanding in contexts such as sustainable tourism, where consumer–brand relationships are multidimensional, evolving, and embedded in both cognitive and affective processes.

4. Results

4.1. Participants’ Profile

According to

Table 1. Participants’ profile.

Participants’ Profile		Freq.	%
Gender	Male	512	58%
	Female	370	42%
Age	Less than 25 years	44	5%
	From 25 to less than 35 years	281	31.9%
	From 35 to less than 45 years	255	28.9%
	From 45 to less than 55 years	215	24.3%
	55 years and above	87	9.9%
Educational level	Less Bachelor	152	17.2%
	Bachelor	642	72.8%
	Postgraduate	88	10%

, the demographic results indicate a predominance of male participants, who comprised 58% of the sample, compared to 42% female respondents. In terms of age distribution, the largest age group was those aged 25 to less than 35 years (31.9%), followed by participants aged 35 to less than 45 years (28.9%), and those in the 45 to less than 55 years category (24.3%). A smaller segment of the sample fell into the 55 years and above group (9.9%), while the youngest group, under 25 years of age, accounted for only 5%. Regarding educational attainment, a significant majority of respondents held a bachelor’s degree (72.8%). Participants with less than a bachelor’s qualification represented 17.2%, while those with postgraduate degrees made up 10% of the sample.

4.2. Measurement Model

The assessment of the measurement model demonstrated strong psychometric properties across all constructs, indicating that the scales used in this study were both reliable and valid. As indicated in

Table 2. Measurement model.

Construct	Loading	Cronbach Alpha	CR	AVE	VIF
Green Marketing		0.843	0.924	0.802	3.019
Green marketing1	0.879
Green marketing2	0.911
Green marketing3	0.898
Brand engagement		0.857	0.928	0.765	2.675
Brand engagement1	0.870
Brand engagement2	0.865
Brand engagement3	0.871
Brand engagement4	0.894
Green brand trust		0.822	0.944	0.772	2.445
Green brand trust1	0.909
Green brand trust2	0.887
Green brand trust3	0.847
Green brand trust4	0.860
Green brand trust5	0.891
Green purchase intention		0.856	0.936	0.746	2.239
Green purchase intention1	0.880
Green purchase intention2	0.867
Green purchase intention3	0.848
Green purchase intention4	0.866
Green purchase intention5	0.859

, all standardized factor loadings exceeded the recommended threshold of 0.70, with values ranging from 0.847 to 0.911, reflecting high item reliability and substantial contribution of each item to its respective construct. Internal consistency was further supported by Cronbach’s Alpha values ranging from 0.822 to 0.857, which exceed the minimum acceptable benchmark of 0.70, affirming the internal reliability of the scales. Composite reliability (CR) values for all constructs were also well above the recommended threshold of 0.70, ranging from 0.924 for green marketing to 0.944 for green brand trust, indicating excellent construct-level consistency. Similarly, the Average Variance Extracted (AVE) values were all above the acceptable level of 0.50, with scores ranging from 0.746 to 0.802, confirming adequate convergent validity and that a substantial proportion of variance in each construct was explained by its indicators [102].

Multicollinearity was evaluated using the Variance Inflation Factor (VIF), and all constructs reported VIF values below the critical threshold of 5, with the highest being 3.019, suggesting that collinearity was not a concern and the structural relationships among constructs can be interpreted without distortion due to redundancy. In addition to reliability and validity indicators, the overall goodness-of-fit of the measurement model was confirmed through a series of model fit indices. The value of CMIN/DF = 2.098 indicated a satisfactory level of model parsimony and fit. Complementary indices further reinforced the robustness of the model: GFI = 0.947, AGFI = 0.944, NFI = 0.950, IFI = 0.955, CFI = 0.951, and TLI = 0.949—all of which exceeded the conventional threshold of 0.90, confirming an excellent fit between the hypothesized model and the observed data. Furthermore, the RMSEA value of 0.022, which falls well below the acceptable upper limit of 0.08, provided strong evidence for the model’s close fit and low approximation error [104].

Collectively, these results provide substantial empirical support for the measurement model, confirming that the constructs are measured with a high degree of reliability, validity, and statistical adequacy, and are therefore suitable for further structural analysis [103].

The discriminant validity of the measurement model was assessed using both the Fornell–Larcker criterion and the Heterotrait–Monotrait Ratio (HTMT), two widely accepted techniques for evaluating whether constructs are empirically distinct from one another. According to the Fornell-Larcker criterion, discriminant validity is established when the square root of the Average Variance Extracted (AVE) for each construct exceeds the correlations it shares with other constructs in the model. As shown in the results, the diagonal values representing the square roots of the AVEs were consistently higher than the corresponding off-diagonal correlations. For example, the square root of the AVE for green marketing was 0.896, which exceeds its correlations with brand engagement (0.603), green brand trust (0.555), and green purchase intention (0.707). A similar pattern was observed for all other constructs, including brand engagement (0.875), green brand trust (0.879), and green purchase intention (0.864), thus confirming discriminant validity across the model (

Table 3. Discriminant validity.

	Green Marketing	Brand Engagement	Green Brand Trust	Green Purchase Intention
Green marketing	0.896
Brand engagement	0.603	0.875
Green brand trust	0.555	0.521	0.879
Green purchase intention	0.707	0.448	0.550	0.864

) [103].

Further validation was performed using the HTMT ratio, which assesses the similarity between constructs based on trait correlations. All HTMT values were found to be below the conservative threshold of 0.85, indicating strong evidence of discriminant validity (

Table 4. HTMT for validity.

	Green Marketing	Brand Engagement	Green Brand Trust	Green Purchase Intention
Green marketing
Brand engagement	0.451
Green brand trust	0.348	0.567
Green purchase intention	0.448	0.521	0.498

). Specifically, the HTMT values between green marketing and brand engagement (0.451), green brand trust (0.348), and green purchase intention (0.448) were all comfortably within acceptable limits. Likewise, the HTMT ratio between brand engagement and green purchase intention (0.521) and between green brand trust and purchase intention (0.498) also remained well below the threshold, reinforcing the distinctiveness of the constructs [104]. Together, these results confirm that each latent variable captures a unique dimension within the model and is empirically separable from the others. The strong discriminant validity demonstrated here further enhances the credibility of the measurement model and ensures the appropriateness of proceeding to the structural model analysis [103].

4.3. Structure Model

The structural model yielded statistically robust results, offering strong empirical support for all hypothesized relationships.

Table 5. Structure model.

Path	β	s.e	C.R	p-Value	Results
Direct path
H1: Green marketing → Green purchase intention	0.487	0.048	10.14	0.000	Supported
H2: Green marketing → Brand engagement	0.412	0.055	7.49	0.000	Supported
H3: Brand engagement → Green purchase intention	0.398	0.050	7.96	0.000	Supported
H4: Green marketing → Green brand trust	0.501	0.059	8.49	0.000	Supported
H5: Green brand trust → Green purchase intention	0.446	0.048	9.29	0.000	Supported
Mediation path
H6: Green marketing → Brand engagement → Green purchase intention	0.164	0.030	5.47	0.000	Supported
H7: Green marketing → Green brand trust → Green purchase intention	0.223	0.036	6.19	0.000	Supported

highlighted that the direct effect of green marketing on green purchase intention (H1) was found to be positive and significant (β = 0.487, C.R = 10.14, p < 0.001). Furthermore, green marketing was shown to have a significant direct impact on both brand engagement (H2: β = 0.412, C.R = 7.49, p < 0.001) and green brand trust (H4: β = 0.501, C.R = 8.49, p < 0.001). In parallel, the effects of brand engagement on green purchase intention (H3) and green brand trust on green purchase intention (H5) were also statistically significant (β = 0.398 and 0.446, respectively; both p < 0.001).

Crucially, the analysis of the mediating pathways revealed significant indirect effects in both hypothesized mediation scenarios as depicted in Table 5. The indirect path from green marketing to green purchase intention through brand engagement (H6) was statistically significant (β = 0.164, C.R = 5.47, p < 0.001), as was the path mediated through green brand trust (H7: β = 0.223, C.R = 6.19, p < 0.001). Given that the direct path between green marketing and green purchase intention (H1) remained significant even after including the mediators, both brand engagement and green brand trust function as partial mediators in the model. This indicates that while each mediator accounts for a substantial portion of the effect, green marketing also exerts a residual direct influence on purchase intention. Collectively, these findings support a nuanced mediation structure, whereby green marketing influences tourist behavior both directly and indirectly through distinct psychological mechanisms—emotional involvement with the brand and trust in its environmental integrity. This confirms the theoretical proposition that effective green marketing operates not merely through message exposure, but through the cultivation of deeper brand–consumer relationships that ultimately drive sustainable purchase intentions.

5. Discussion

The current study set out to examine the mechanisms through which green marketing influences tourists’ intention to adopt environmentally responsible purchasing behavior, with a particular focus on the mediating roles of brand engagement and green brand trust. The results confirmed that green marketing positively affects green purchase intention. This aligns with the findings of [6,18,49], who showed that sustainability-oriented marketing enhances environmental awareness and stimulates pro-environmental consumption. Further, refs. [53,54] demonstrated that when campaigns are well-positioned and aligned with ecological values, they can effectively shift consumer intentions across diverse contexts. The contribution of the present study lies in situating these effects within tourism, a sector where services are intangible and authenticity is decisive. In this setting, sustainability messages are not peripheral but central drivers of purchase intentions, adding nuance to earlier research that largely focused on consumer goods.

The study also found that green marketing strengthens brand engagement. Prior studies confirmed that credible and value-driven sustainability communication enhances consumer involvement [19,59,60]. This study advances those findings by showing that in tourism, engagement reflects more than message receptivity. Tourists actively internalize sustainability narratives as part of their identity and emotional bond with the brand, positioning engagement as a relational and identity-based process that extends beyond prior descriptive accounts.

Moreover, the results revealed that brand engagement positively affects green purchase intention. This is consistent with previous studies [14,63,68], which all confirmed the positive association between engagement and pro-environmental purchasing. What the current study adds is evidence from tourism, where engagement operates not only as a behavioral predictor but also as a bridge between sustainability messaging and consumers’ self-concept. This reinforces the idea that green purchase intention is shaped by deeper psychological involvement rather than simple attitude change.

The findings also confirmed that green marketing enhances green brand trust, in line with prior research showing that transparent and consistent environmental claims strengthen consumer confidence [6,80,81]. This study expands the discussion by highlighting that in tourism—where consumers cannot directly verify environmental practices and where the risk of greenwashing is high—trust plays an amplified role as a safeguard. Trust becomes a decisive mechanism that transforms marketing claims into credible commitments, thereby reducing uncertainty and enabling action.

Finally, the results demonstrated that green brand trust has a positive effect on green purchase intention. This relationship is widely supported in the literature [23,82,86,87]. The present study contributes by reinforcing this evidence in the tourism sector, showing that trust serves as psychological assurance that bridges ecological values and actual behavior. In contexts where direct verification of sustainability practices is difficult, tourists rely heavily on trust to justify eco-friendly choices, thereby underscoring its critical role as a determinant of purchase intention.

Finally, the results concluded that brand engagement and green brand trust partially mediate the link between green marketing and green purchase intention. This partial mediation confirms that while green marketing has a direct effect on intention, its influence is significantly strengthened when tourists also experience psychological involvement and relational confidence in the brand. The dual mediation pathway provides a more nuanced understanding of how sustainability messages are internalized—not just cognitively, but emotionally and ethically. In the context of partial mediation, this means that although brand engagement and green brand trust explain a substantial portion of the relationship, other variables may also play a role in shaping tourists’ purchase intentions. Factors such as environmental awareness, prior green consumption experience, cultural values, or perceived risks of greenwashing could further influence the strength of these relationships. This interpretation highlights that effective green marketing is not solely a matter of message delivery, but a process of cultivating meaningful consumer–brand relationships rooted in shared values and credibility, while also leaving room for future studies to examine additional mediators and moderators that could enrich the model.

6. Theoretical Implications

The findings of this study offer several theoretical implications, particularly for advancing and contextualizing the Theory of Planned Behavior (TPB) and attachment theory in sustainable tourism. By validating the effects of green marketing on green purchase intention, brand engagement, and green brand trust, the study both confirms existing assumptions and extends the conceptual scope of these frameworks.

First, the confirmation that green marketing positively affects purchase intention contributes to TPB by showing how attitudinal components are shaped in value-driven contexts. While TPB emphasizes attitudes, norms, and perceived control as antecedents of intention, it often underrepresents marketing stimuli as catalysts. Unlike earlier applications of TPB that focused mainly on consumer goods or general environmental behavior, this study demonstrates its relevance in the tourism sector, where decision-making involves symbolic meaning and experiential value. The current findings suggest that green marketing functions as a formative external influence, shaping favorable attitudes toward pro-environmental behavior. This contrast highlights how TPB can be extended from rational predictors toward communication-based and value-laden triggers of intention in service-oriented contexts.

Second, the positive effect of green marketing on brand engagement and trust adds depth to attachment theory. Traditionally, the theory highlights emotional bonds formed over time, yet the results show that sustainability-oriented communications can trigger early engagement and trust even before consumption. This contrasts with prior research that positioned attachment as a post-consumption outcome; our findings show that it can emerge in pre-purchase stages when marketing messages align with authenticity and consumer values. This extends the theory’s relevance by revealing that attachment can be strategically cultivated through communication, not only through prolonged interaction.

Moreover, the finding that engagement and trust both influence purchase intention extends TPB beyond its cognitive foundations. Intention is shown to stem not only from rational evaluation or normative pressure but also from relational and emotional alignment. This diverges from traditional TPB studies, which tended to privilege cognitive drivers, by demonstrating that affective and credibility-based mechanisms are equally important in shaping intention in sustainable tourism. Introducing engagement and trust as antecedents highlights the role of affective and credibility-based mechanisms, suggesting that TPB should incorporate relational variables as integral to intention formation, especially in sustainability-driven contexts.

Critically, the mediating roles of engagement and trust advance both theories. For TPB, they reveal an indirect route through which green marketing shapes intention—via psychological and emotional bonds—introducing an affective-relational layer to a traditionally rational model. For attachment theory, the findings show that attachment-relevant constructs can emerge not only through prolonged experience but also through strategic communication that reflects consumer values. This adds nuance to prior attachment research by emphasizing that in sustainability-driven tourism, brand trust and engagement function as accelerated pathways to attachment.

Collectively, these findings validate and expand both frameworks by showing how green marketing operates simultaneously as a behavioral trigger and a relational builder. In contrast to previous studies that treated these mechanisms separately, this study integrates them, bridging intention-based and emotion-based models. The result is an enriched theoretical perspective that better reflects the complexity of decision-making in sustainability-driven tourism.

7. Practical Implications

The results of this study provide actionable insights for tourism businesses, destination marketers, and sustainability-driven organizations seeking to influence environmentally conscious travelers. Evidence that green marketing shapes purchase intention—both directly and through relational mechanisms—requires a strategic shift in how sustainability communication is approached. Green marketing should not be treated as an auxiliary effort but positioned as a core strategic function integrated with brand identity, service design, and guest experience. This involves value-infused communication that moves beyond declaring credentials to narrating ecological purpose through storytelling, experiential messaging, and emotional resonance.

The finding that green marketing enhances brand engagement suggests that firms should move from one-way promotion to co-creative platforms. Inviting tourists into the sustainability journey—through participatory programs, interactive content, or transparent behind-the-scenes initiatives—transforms passive audiences into active stakeholders. Such practices deepen emotional investment and reinforce the tourist’s role in co-producing environmental value.

Given the pivotal role of trust, symbolic gestures or vague claims are no longer sufficient. Trust must be earned through transparency and verification. Tourism brands should invest in credible certifications, publish carbon accounting data, and adopt verifiable reporting systems, such as blockchain-backed tools. These steps shift trust from persuasion to demonstrable proof, reinforcing confidence in purchase decisions. The dual mediating role of engagement and trust also highlights the need for integrated strategies. Managers should design experiences where every touchpoint—from pre-trip communication to post-trip feedback—reinforces both emotional relevance and credibility. Embedding sustainability narratives into guest journey maps or aligning eco-initiatives with service protocols ensures consistency across the customer lifecycle.

Beyond managerial practice, these findings speak directly to academic debates on greenwashing, authenticity, and consumer scepticism. The results show that consumer trust is highly contingent on the perceived authenticity of sustainability claims. This highlights that green marketing should not merely aim to persuade but to withstand scrutiny under conditions of scepticism. By demonstrating how engagement and trust mediate the impact of green marketing, this study provides empirical support for strategies that reduce the risk of greenwashing accusations and address consumer doubts proactively. In doing so, it bridges practice and theory: it suggests that authenticity is not only a reputational concern but also a structural driver of sustained consumer behavior in green tourism.

Likewise, sustainability marketing should be reoriented from reputational goals to behavioral activation and long-term loyalty. Data-driven personalization of green offerings, based on psychographic profiles, enables brands to match sustainability messages with consumer mindsets. Moving from generic appeals to targeted relational messaging transforms sustainability into a dynamic, personalized value proposition that strengthens repeat purchase intention and advocacy.

In summary, while these implications provide concrete guidance for tourism managers, they also extend to wider academic debates by illustrating how green marketing can be implemented without falling into the pitfalls of greenwashing, how authenticity can be operationalized as a measurable brand asset, and how consumer scepticism can be mitigated through transparent, verifiable practices. This dual orientation ensures that the study’s practical recommendations also contribute meaningfully to scholarly discussions on sustainable marketing and consumer trust.

8. Limitations and Future Research

While this study provides meaningful theoretical and practical contributions, it is important to acknowledge certain limitations that shape the boundaries of its generalizability and open new directions for future research. First, the study focused exclusively on tourists as the unit of analysis, examining their responses to green marketing efforts initiated by tourism brands. While this perspective offers valuable insights into consumer behavior, it does not capture the organizational strategies, operational constraints, or internal sustainability philosophies of tourism providers themselves. Future research could adopt a multi-stakeholder approach, incorporating perspectives from destination management organizations, travel agency executives, and sustainability officers to better understand how institutional commitment interacts with consumer perception in driving green behavior.

A second limitation lies in the cross-sectional nature of the research design, which captures tourists’ perceptions and intentions at a single point in time. As green marketing often builds its influence cumulatively—through repeated exposure, brand experience, and evolving trust—this design may not fully capture the temporal development of brand relationships. Longitudinal studies that track tourists’ engagement, trust formation, and behavioral shifts over time could provide deeper insights into how green brand dynamics evolve across the pre-, during-, and post-travel phases.

Thirdly, the study adopted a quantitative approach using structured scales, which allowed for statistical rigor but may have limited the depth of insight into the nuanced psychological processes underpinning trust and engagement. Future research could enrich this field by embracing qualitative or mixed-method designs, incorporating in-depth interviews, narrative inquiry, or ethnographic observation to uncover the subtle emotional, cultural, and symbolic meanings that tourists associate with green brands.

An additional limitation stems from the specific mediators selected in this study—namely, brand engagement and green brand trust. While both variables offer strong explanatory power within relational and psychological frameworks, they do not exhaust the spectrum of mechanisms that may shape the relationship between green marketing and green purchase intention. Other cognitive and emotional constructs—such as perceived brand authenticity, environmental self-identity, or moral obligation—may play critical mediating roles. Future research should explore alternative or parallel mediators, particularly those rooted in environmental psychology and ethical consumption theory, to reveal more layered and potentially culture-sensitive pathways linking green communication to behavioral outcomes.

With respect to the dependent variable, the focus of this study was limited to green purchase intention, a construct that, while widely accepted as a predictor of behavior, does not always translate into actual consumer action. The well-documented intention–behavior gap in sustainability research suggests that other post-intentional variables—such as follow-through behavior, repeat booking, or eco-loyalty—deserve further exploration. Future research could extend the model to examine actual green behavior in tourism settings, using observational methods, behavioral tracking, or longitudinal follow-up to assess whether intentions generated by green marketing translate into sustained, real-world outcomes.

Another limitation of this study is that it did not consider demographic characteristics such as age, gender, income, or educational background, which may influence or moderate the relationships among green marketing, brand engagement, green brand trust, and purchase intention. Future research is encouraged to incorporate these demographic variables to determine whether the observed relationships hold consistently across different consumer groups or vary according to specific demographic profiles.

Additionally, this study relied on self-reported data, which may introduce bias, particularly social desirability effects that could lead respondents to overstate their pro-environmental attitudes or intentions. Future research could mitigate this by triangulating survey responses with behavioral or observational data to validate the accuracy of self-reported measures.

Finally, the study employed a purposive, non-probabilistic sampling strategy in a specific cultural context. While this approach allowed us to capture relevant insights from targeted respondents, it limits the statistical generalizability of the findings beyond the surveyed population. Future research should adopt probability-based sampling methods or larger, more diverse samples across different cultural settings to strengthen both the external validity and cross-cultural applicability of the results.