Mutual Agreement Procedures (MAP): OECD Publishes New Manual For Effective International Tax Disputes

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On 2 February 2026, the Organisation for Economic Co-operation and Development (OECD) published an updated edition of the Manual on Effective Mutual Agreement Procedures (MEMAP).

This is the first comprehensive revision of the MEMAP since it was originally released in 2007 and marks another step in the OECD’s ongoing efforts to enhance international tax dispute resolution as part of the broader tax certainty agenda.

What is MAP?

The OECD MAP is a dispute resolution mechanism under Article 25 of the OECD Model Tax Convention. It allows taxpayers to seek resolution when they believe that actions by one or both Contracting States result, or will result, in taxation that is not in accordance with the provisions of an applicable tax treaty. MAP is frequently used to address potential double tax risk arising from transfer pricing adjustments and disputes over permanent establishment status. MAP can also cover a multitude of other issues, including:

dual residence;
withholding tax;
payment characterisation;
non-discrimination; and
cross-border workers.

A taxpayer who believes that they have been, or will be, taxed contrary to a tax treaty may present their case to their jurisdiction’s competent authority (the officials responsible for administering tax treaties, including reviewing and negotiating MAPs). In the UK, this means HMRC.

In terms of timing, in most cases requests must be made within three years from the first notification of the “action” giving rise to the disputed taxation (such as a closure notice for a tax assessment). It is also worth keeping in mind that an action may also include taxpayer-initiated adjustments.

Key features of the 2026 MEMAP

In 2024, the OECD surveyed a number of competent authorities, businesses, and tax advisors to identify what worked well in MAP, what were the key frustrations in MAP, and what improvements were needed. Drawing on this feedback, the revised MEMAP builds on the 2007 original to provide a practical guide for all parties navigating the MAP process.

The revised edition broadly follows the different phases of a MAP case chronologically, from initiation through to resolution. The MEMAP is now organised into three main chapters, each addressing a distinct phase of the MAP lifecycle as well as a fourth chapter addressing considerations for jurisdictions with low-capacity resources.

Chapter 1: dispute prevention and competent authority organisation (pre-MAP phase)

Chapter 1 of the guidance focuses on preventing international tax disputes before they arise and resolving them fairly through MAP when they do. Tax authorities are encouraged to use proactive tools such as advance pricing agreements (APAs) to help businesses avoid disputes altogether.

Where a MAP is sought, the MEMAP recommends that tax authorities be organised such that the team handling the MAP case (the competent authority) is separate from the team that conducted the original tax enquiry. This separation helps ensure impartiality. Moreover, the MEMAP encourages competent authorities to adopt a fair and pragmatic approach, proposing reasonable outcomes and being willing to compromise, with the aim of building trust between countries and taxpayers, leading to quicker and fairer resolutions.

Chapter 2: access to MAP and unilateral relief (unilateral phase)

In a typical MAP case, the competent authorities of both contracting states engage in negotiations to resolve the double taxation issue. However, competent authorities can, and sometimes do, provide relief unilaterally.

The MEMAP encourages competent authorities to consider whether unilateral relief can be provided in more cases, particularly in less complex cases. An aspirational target has been set which aims for a competent authority to decide whether it can provide unilateral relief and inform the taxpayer and the other competent authority within four months of receiving a complete MAP request and all necessary information.

Tax authorities are encouraged to not unduly prevent taxpayers from accessing MAP (e.g. by not applying overly strict interpretations of time limits for MAP applications). The chapter also calls out other practices adopted by some tax authorities that make it difficult for taxpayers to access MAP (including threats of penalties or commencement of criminal proceedings to deter pursuit of MAP) but notes that progress has been made in many countries to address this issue.

Chapter 3: bilateral discussions and MAP arbitration (bilateral phase)

When tax authorities cannot resolve a dispute unilaterally, they enter bilateral negotiations. This typically involves three steps:

exchanging position papers and holding discussions;
finalising and implementing any agreement reached; and
if no agreement is reached, the taxpayer may request arbitration (where the treaty allows).

The guidance emphasises that meetings should be collaborative, pragmatic and focused on finding solutions. In particular, competent authorities should not be attempting to re-audit any positions but rather verifying whether a resulting adjustment or assessment aligns with the relevant tax treaty, only seeking factual clarifications where needed.

For taxpayers, it is important to note that MAP is undertaken on a “best endeavours” basis, with no strict guarantee of full resolution (e.g. full elimination of double taxation). While this can be a source of uncertainty and frustration for taxpayers, the positive statistic is that, based on 2024 data, only 4% of MAP cases were closed without agreement.

MAP arbitration acts as a final safety net if authorities cannot agree an answer. In such cases, any remaining issues may be submitted to arbitration at the request of the taxpayer. Arbitration decisions are binding on both countries. Not all countries include arbitration provisions in their treaties, but for UK taxpayers, arbitration is generally available through the UK's treaty network (in fact, it is UK policy¹ to include a provision for arbitration in its double tax treaties).

Chapter 4: considerations for low-capacity jurisdictions

Chapter 4 addresses the needs of low-capacity jurisdictions, recommending that, where possible, jurisdictions with more extensive MAP experience invest in capacity-building initiatives to support competent authorities in jurisdictions with little or no MAP experience. This is in the spirit of the OECD’s “Tax Inspectors Without Borders” model.

MEMAP best practices

Running through the spine of the manual are the 59 aspirational best practices identified by the OECD, which were developed directly from input from both tax administrations and businesses.

Of these 59 best practice suggestions, nine are directed at taxpayers, with the remaining 50 aimed at tax authorities. This allocation reflects that whilst MAP is fundamentally a government-to-government process, taxpayers still have a meaningful role to play in ensuring that cases proceed efficiently and effectively.

For taxpayers, best practice guidance focuses on entering and engaging in the MAP process in good faith, making every effort to provide full and complete information to all parties involved. This includes providing comprehensive information to tax authorities during local tax enquiries, rather than holding back data or analysis to deploy strategically in subsequent MAP proceedings. The MEMAP also encourages taxpayers to submit MAP requests as soon as possible after receiving notification of an action they believe results in taxation not in accordance with a tax treaty, and to provide information in a simple and understandable format to avoid delays in processing. Taxpayers should also make themselves available for communications, calls, and meetings with competent authorities throughout the MAP process to support the efficient, effective, and timely handling and resolution of cases.

Good faith engagement with the MAP (MEMAP Best Practice Nº18)	Timely submission of MAP requests (MEMAP Best Practice Nº22)	Clear and simple format for MAP requests (MEMAP Best Practice Nº24)
Actively cooperate, provide information promptly, and submit MAP requests in a timely manner after reviewing published guidance. Clearly mark protective requests, act consistently with chosen remedies, and accept agreements that fully resolve treaty-inconsistent taxation.	Submit MAP requests as soon as possible after receiving notification rather than waiting until filing deadlines. Provide all necessary information and translations upfront in complex cases to enable faster resolution.	Provide required information in a MAP request in a simple and understandable format, with clear main text and supporting annexes to avoid processing delays. Include Executive Summaries for complex cases and provide translations in English (or another mutually agreed language) where authorities do not share a common language.
Protective MAP requests (MEMAP Best Practice Nº25)	Timely responses during MAP process (MEMAP Best Practice Nº36)	Availability for communications (MEMAP Best Practice Nº45)
Clearly mark requests as protective to preserve time limits without triggering substantive examination until expressly requested. Avoid requesting MAP suspension after substantive discussions begin to pursue domestic remedies.	Provide timely and complete responses to requests for additional information. Ensure both competent authorities receive identical details simultaneously.	Remain available for communications, calls, and meetings throughout the MAP process. This cooperative approach enables clarifications and prevents delays in case resolution.
Responding to provisional MAP agreements (MEMAP Best Practice Nº49)	Arbitration (MEMAP Best Practice Nº54)	Providing MAP requests to both jurisdictions (MEMAP Best Practice Nº23)
Confirm agreement or disagreement within specified timeframes, provide any reasonable information request, and withdraw/waive domestic remedies to allow implementation. Cases may be closed if consent and withdrawals are not obtained despite reasonable follow-up.	Assess whether to continue productive MAP discussions beyond arbitration deadlines or proceed to arbitration. Weigh the time and effort required for arbitration against the likelihood of achieving resolution through continued discussions.	Submit MAP requests to both jurisdictions concerned, either formally or by having only one MAP request submitted formally to the competent authority of the taxpayer’s state of residence as required under the treaty, while providing a copy to the other. Include checklists that demonstrate how the information provided corresponds to the information requirements in both jurisdictions.

Useful guides and templates for taxpayers and competent authorities

In addition to the best practices, the MEMAP provides a number of templates that both taxpayers and competent authorities can utilise, including those for MAP requests, position papers, and closing letters.

The importance of MAP in today's tax environment

The 2024 MAP statistics² published by the OECD demonstrate both the value and the ongoing challenges of the MAP process. The average time to conclude a MAP case currently stands at 27.8 months, though transfer pricing cases continue to take somewhat longer at 30.9 months, significantly above the 24-month target set by the OECD.

MAP remains a very important tool for UK taxpayers. The latest statistics published by HMRC³ show it resolved 115 MAP cases in 2024/25. This is a significant increase from the 86 cases resolved in 2023/24, but a decrease from the 131 cases resolved in both 2021/22 and 2022/23. On a positive note, the average time to resolve MAP cases by HMRC was 24.8 months in 2024/25, far better than the 30.9-month average reported by the OECD.

Though MAP resolution undoubtedly takes a long time, encouragingly, the OECD statistics also show that a high proportion of cases reach full or partial resolution (approximately 73% of MAP cases in 2024 reached full resolution through a competent authority agreement, unilateral relief, or domestic resolution). As mentioned above, with only 4% of cases closed without reaching some sort of resolution there is clearly willingness from competent authorities to reach agreements in most cases. It is very much a message of patience and “trust the process” for taxpayers.

Overall, the publication of the 2026 MEMAP represents a constructive and practical step forward in international tax dispute resolution. Whilst the manual is non-binding, and jurisdictions are not compelled to adopt all or any of the OECD’s recommendations and best practices, it nonetheless provides a valuable framework for improving the efficiency and effectiveness of MAP globally. While there remains work to be done, the updated guidance provides both competent authorities and taxpayers with more tools to work towards faster and fairer resolutions on cross-border disputes.

Footnotes

1. NTM423080 - Transfer pricing: methodologies: Mutual Agreement Procedure: Arbitration - HMRC internal manual GOV.UK

2. 2024 Mutual Agreement Procedure Statistics | OECD

3. Transfer Pricing and Diverted Profits Tax statistics: 2024 to 2025 - GOV.UK

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