Invoicing FAQ

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If you are unable to resolve the issue, please see our Payment Instructions for alternative payment options.

MDPI allows the corresponding and submitting author to update the invoice information by following the link provided in the invoice email or in the Submissions Menu under Invoices.

You can modify the billing address, email address and invoice currency. Please note that the modified invoice can be downloaded immediately after the update.

It is possible to split a single invoice into up to eight parts. Please send your request to ✉️ and specify how many parts you would like the invoice split into, and provide a new billing address for each part. Please note that each part will have its own new ID and a payment link for online settlement.

We accept payments in Swiss francs (CHF), US Dollars (USD), Euros (EUR), Pounds Sterling (GBP), Japanese Yen (JPY) and Canadian Dollars (CAD). For more detailed information, please visit our Payment Instructions.

You may change the currency of the invoice by using the link provided in your APC Invoice email or accessing the invoice through your profile under the Submissions Menu in Invoices.

MDPI has an Institutional Open Access Program (IOAP) which grants authors affiliated with participating institutions discounts on our APC.

Reviewers who provide timely and substantial comments will receive a discount voucher code entitling them to an APC reduction. Vouchers will be sent to reviewers only after the final decision of the reviewed paper is given. All valid and associated vouchers can be applied to one invoice.

Note that vouchers issued to specific individuals are not transferable. Only vouchers that were issued to one of the authors of the current paper are valid and must be mentioned during the submission process.

Please note that reviewer vouchers must be applied before acceptance for publication. Vouchers can no longer be applied once an APC invoice has been issued

Discount vouchers will be shown under the Submissions Menu in the Discount Vouchers list. In order to be able to use all vouchers sent from MDPI, authors are allowed to link multiple emails to the current profile being used.

Please add your voucher code in the MDPI system when you submit your paper, then, you will automatically receive a reduction on the APC.

Note that vouchers cannot be used after an invoice has been issued. In case of rejection, the voucher can be reapplied in your next submission. If you are not sure how to apply your voucher, please contact the assigned editor.

Authors affiliated with participating universities receive up to one IOAP discount on the APC for any paper published in an MDPI journal which may be combined with reviewer vouchers.

The Editorial Office informs the MDPI Accounts Department on the APC for each paper. The APC can no longer be changed once a paper has been accepted for publication. Therefore, please confirm the APC with your Assigned Editor during the APC confirmation stage (including any applicable discount).

Please note that it may take several days for a bank transfer to be registered. Please make sure to include the invoice ID in the payment (e.g. invoice ID: journalname-123456). If your payment was not confirmed, please send a valid proof of payment to ✉️.

If your initial payment was incomplete (e.g. not including the 5% fee for PayPal payments), another invoice will be issued to you for the remaining amount.

In case you accidentally pay more than invoiced by MDPI, please contact us at ✉️ and we will refund the overpaid amount, minus any bank or transaction charges.

MDPI provides an option for payment in advance if the customer’s budget funds may expire before the final decision of the paper is provided. Such agreements should be organized with the Editorial Office of the relevant Journal. The MDPI Accounts Department will send an invoice (proforma) in advance if requested. Please note that any advance payment will not affect the final decision as to whether an article is accepted for publication.

Please contact ✉️ and indicate in which journal you would like to submit a paper and provide your billing address.

If the paper is rejected, MDPI will issue a refund upon request after deducting the bank fees, or you could choose to keep the amount as pre-payment for another publication.

Please note that APCs will not be refunded due to the retraction of an article.

If a paper has been accepted the payment is non-refundable. In the event that a manuscript is withdrawn by author request after it has been accepted any payment made may only be used as credit on a future submission.

No. MDPI only sends the invoice for article processing charges (APCs) if a manuscript has been accepted for publication. The acceptance of a manuscript is based on the outcome of the peer-review procedure. The final decision as to whether a manuscript will be accepted for publication or rejected is made by an external editor (usually the Editor-in-Chief of a journal or the Guest Editor of a Special Issue) generally based on scientific merit.

Yes, we accept Purchase Orders (PO’s). Please send your PO’s to ✉️ and indicate the invoice/manuscript ID in the subject line.

We are already using several platforms for e-invoicing. It is mandatory to send all the required information or codes per email, otherwise we will not be able to provide the correct invoice. We use a B2B Router platform, Chorus Pro (for French subjects) and Coupa.

It is important to indicate the invoice/manuscript ID in the subject line, in case a reply is needed.

All quoted APCs are exclusive of VAT. With the exception of customers residing in Switzerland or Japan, no VAT will be added to invoices. Authors should account for the VAT in their country under the reverse charge mechanism, whereby the recipient of a service from a foreign company pays the VAT directly to the local tax office. Please check with your institution for guidance on local VAT.

The Japanese Consumption Tax (JCT) at the rate set by the Japanese government shall be added to the invoices for residents in Japan.

Please contact MDPI Accounts Department ✉️ for further questions. If your paper has already been submitted, please indicate your invoice/manuscript ID.