Dispute prevention and resolution are essential to help preserve trust in the tax systems. This chapter explores the strategies put in place by tax administrations to resolve and prevent disputes fairly and efficiently, and looks at tax administration performance in dispute resolution.
Tax Administration 2025
Comparative Information on OECD and other Advanced and Emerging Economies
Abstract
Taxpayer rights and obligations are frequently set out in law or taxpayer charters. Table 8.1. sets out some of the most commonly reported rights and obligations. Underpinning these rights and obligations is access to processes that allow taxpayers to effectively challenge assessments and decisions, which helps safeguard taxpayer rights and ensures that appropriate checks and balances exist on the exercising of tax powers by administrations. At the same time, tax administrations and taxpayers should also strive to work together to prevent disputes from arising in the first place, thus reducing burdens and uncertainty for both parties.
This chapter examines the dispute resolution and review strategies in the jurisdictions covered by this report, as well as their performance in this area. This is an important function of tax administrations, and on average close to 6% of total staff numbers are dedicated to the management of disputes, including litigation, dispute resolution, appeals, objections and rulings (see Chapter 9).
All 58 jurisdictions covered in this report provide taxpayers with the right to challenge assessments. Almost all administrations report having an internal review mechanism in place, and most provide taxpayers with the option to seek an independent review by an external body, which can help improve legal certainty for taxpayers while avoiding potentially lengthy and costly legal proceedings. For those administrations that offer both review mechanisms, 75% require taxpayers to seek an internal review before their case can be reviewed by an external body. (See Table 8.2.)
Percentage of administrations
Source: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Tables A.89 Dispute resolution: Review mechanisms, and A.90 Dispute resolution: Review procedure, http://isoradata.org (accessed on 1 October 2025).
Performance in dispute resolution
While tax administrations cannot generally control the timing of judicial processes, many of them are working on improving dispute resolution processes to make them quicker. These might include mediation or other non-judicial routes, as well as improvements to case management systems as shown in the example in Box 8.1.
HMRC have built and implemented a bespoke litigation case management system, available on a platform shared with other HMRC systems. This gives the capability to connect data and systems across the administration, enabling HMRC to track the life cycle of compliance activity from initiation through to dispute resolution. Cases can be tracked using different identifiers to support the identification of patterns and trends, and the information is available to users across HMRC.
The model was developed by a cross-HMRC virtual team drawn from the litigation, project management, tax professional and data communities, to bring together all relevant expertise.
As the model continues to develop and data quality continues to improve, it will sit alongside other initiatives to enable a data-led approach to the management of the disputes and tax litigation pipeline. This is part of meeting HMRC’s priority to close the tax gap. The model allows insight to be drawn that supports the identification of opportunities for building operational capability and improving the customer experience, including more upstream resolution, as part of an end-to-end dispute management approach.
Source: The United Kingdom (2025).
Table 8.3. and Table 8.4. compare the change between 2018 and 2023 in the number of review cases initiated and on hand at fiscal year-end, for both internal and external reviews. The reductions in the number of cases initiated, see Table 8.3., that were reported by the majority of administrations during the COVID-19 pandemic cannot be observed anymore. Over the past three years, around half of the administrations saw an increase in the number of cases initiated, while the other half saw decreasing numbers.
In relation to the number of cases on hand at fiscal year-end, see Table 8.4., the majority of administrations continues to report decreasing numbers in between 2022 and 2023, particularly in relation to cases under internal review.
Looking at the 10-year period between 2014 and 2023, data for 34 jurisdictions shows that in two-thirds of administrations the number of cases on hand at year-end decreased, in some cases significantly. (Calculation based on Table A.170 in the 2017 edition (OECD, 2017[1]) and Table A.91 in the ISORA database.)
Percentage of administrations that reported an increase or decrease in the number of cases initiated
Sources: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Tables A.91 Dispute resolution: Number of cases - Tax cases under internal procedures, and A.92 Dispute resolution: Number of cases - Tax cases under independent review by external bodies, http://isoradata.org (accessed on 1 October 2025).
Percentage of administrations that reported an increase or decrease in the number of cases on hand
Sources: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Tables A.91 Dispute resolution: Number of cases - Tax cases under internal procedures, and A.92 Dispute resolution: Number of cases - Tax cases under independent review by external bodies, http://isoradata.org (accessed on 1 October 2025).
Figure 8.1. and Figure 8.2. take a more detailed look at the jurisdiction level data and show the change between 2022 and 2023 in the number of review cases on hand at fiscal year-end, for both internal and external reviews. What is interesting to note are the significant increases in the number of internal review cases reported by a few jurisdictions.
At the same time, it should be pointed out that the volume of cases per jurisdiction varies significantly and where the number of cases is very low there can be significant fluctuations between years. This becomes more evident when looking at Figure 8.3., which highlights the wide differences between jurisdictions in the use of internal review procedures.
Looking at Table 8.5., which shows the average number of internal review cases initiated over the period 2018 to 2023, it can be observed that the average has been stable over the years.
Source: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Table A.91 Dispute resolution: Number of cases - Tax cases under internal procedures, http://isoradata.org (accessed on 1 October 2025).
Sources: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Table A.92 Dispute resolution: Number of cases - Tax cases under independent review by external bodies, http://isoradata.org (accessed on 1 October 2025).
Note: For Saudi Arabia, the “No. of internal cases initiated during the FY per 1 000 active taxpayers” was put in relation to active VAT taxpayers.
Source: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Table D.49 Administrative review cases and litigation, http://isoradata.org (accessed on 1 October 2025).
Note: The table shows the averages for those jurisdictions that were able to provide the information for the years 2018 to 2023. The number of jurisdictions for which data was available is shown in parentheses. Data for Germany was not included as it would distort the results.
Source: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Table D.49 Administrative review cases and litigation, http://isoradata.org (accessed on 1 October 2025).
Different interpretations of tax law by taxpayers and the tax administration are a normal part of tax administration, and it is not uncommon for these differences to become subject to litigation, once the internal and external review procedures have been exhausted. Whilst tax administrations report that disputes are usually resolved without the need for litigation, Figure 8.4. reports the performance of administrations for cases decided upon by the courts. It shows significant differences in the success rate of administrations, although for some jurisdictions the number of cases decided is very low, meaning results can fluctuate significantly between years.
Note: Cases resolved in favour of the administration means those cases where the administration has been successful in more than 50% of the issues contested in each case. For Argentina and Italy see the note in Table A.93.
Source: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Table D.49 Administrative review cases and litigation, http://isoradata.org (accessed on 1 October 2025).
Cross-border business and international labour mobility are increasingly common. This inevitably leads to disputes over which jurisdictions have the right to tax certain types of income. Tax treaties between jurisdictions, also known as double taxation agreements, aim to remove double taxation by setting out mutually agreed rules on the allocation of taxing rights. To address situations where parties involved disagree on the application or interpretation of those rules, many tax treaties include a provision for a Mutual Agreement Procedure (“MAP”) to resolve such disputes, separate from the standard legal remedies available under domestic law.
MAP is crucial for the correct application and interpretation of tax treaties. It ensures that taxpayers who are entitled to treaty benefits are not subjected to taxation that is not in line with the treaty’s terms. It is therefore important to ensure that access to the MAP is readily available and that MAP cases are resolved and implemented promptly and within a reasonable timeframe.
Following the publication of the report Making Dispute Resolution Mechanisms More Effective, Action 14 - 2015 Final Report (OECD, 2015[2]), which contains a BEPS minimum standard on the resolution of treaty-related disputes, OECD/G20 BEPS Inclusive Framework members agreed to:
a peer review process to evaluate the implementation of this standard;
to publish the MAP profile for each jurisdiction; and
to report and publish MAP statistics under the MAP Statistics Reporting Framework.
In addition, since 2023, the OECD has annually released the Consolidated Information on MAPs (CIM), which provides a glimpse into each Inclusive Framework member jurisdiction’s MAP programmes, including the MAP provisions in their tax treaties, links to their MAP guidance and MAP profile, the structure of as well as key contacts in their competent authority function and the evolution of their MAP Statistics over the years. This work, including the MAP profiles and statistics, the peer review reports and the CIM, can be found on the OECD website on Dispute resolution in cross-border taxation (OECD, 2025[3]).
In addition to this, the OECD with the Forum on Tax Administration, has developed tools to assist jurisdictions and taxpayers in navigating the MAP process:
the Manual on Effective Mutual Agreement Procedures (OECD, 2007[4]); and
the Manual on the Handling of Multilateral Mutual Agreement Procedures and Advance Pricing Arrangements: Enhancing Tax Certainty (OECD, 2023[5]).
As disputes can be resource intensive processes, preventing them is the most effective strategy, and a key element in the dispute prevention framework is the provision of guidance and advice to taxpayers. Tax administrations often do this as part of their wider service strategy. This can include putting information and interactive tools on their website, publishing guidelines and taxpayer information briefs, and carrying out educational and business support initiatives (see also Chapter 5). In addition, many administrations offer specific dispute prevention mechanisms and some of those approaches are described in this section.
Rulings
As part of tax administrations’ commitment to give taxpayers certainty of treatment, it is common practice for administrations to set out how they will interpret the laws they administer, and how they will interpret the tax law in particular situations. This takes place through rulings:
A public ruling is a published statement of how an administration will interpret provisions of the tax law in particular situations. They are generally published to clarify application of the law, especially where a large number of taxpayers may be impacted by particular provisions and/or where a provision has caused confusion or uncertainty. Typically, a public ruling is binding on the tax administration if the ruling applies to the taxpayer and the taxpayer relies upon it.
A private ruling relates to a specific request from a taxpayer (or their tax representative) seeking greater certainty as to how the law would be applied by the tax administration in relation to a proposed or completed transaction(s). The objective of private rulings is to provide additional support and certainty to taxpayers on the tax consequences of more complex transactions.
To learn more about which administrations provide rulings, see Table 8.5. of the 2024 edition of this series (OECD, 2024[6]).
In 2024, the Polish tax system underwent a significant change in the handling of its tax rulings to allow for faster processing and response times. Now, documents related to tax rulings can only be submitted electronically through the National Revenue Administration’s secure online systems. Decisions in these matters are also delivered electronically via the same systems.
The transition to handling tax rulings online enables a quicker resolution – taxpayers do not need to physically travel into the office as they can log in and do everything from home, and the service is available 24/7.
This change is aimed at streamlining administrative processes, increasing efficiency and reducing bureaucracy. Submitting applications electronically brings numerous benefits for both the tax administration and taxpayers.
Source: Poland (2025).
Advanced pricing arrangements
Bilateral and Multilateral Advance Pricing Arrangements (“APAs”) are binding arrangements between two or more tax administrations and the taxpayers in relation to a specific issue for a prescribed period. In a growing number of cases, these collaborative APAs have successfully contributed to providing advance tax certainty to both taxpayers and tax administrations, ensuring predictability in the tax treatment of international transactions and reducing potential tax disputes.
To support administrations and taxpayers, the FTA MAP Forum has developed the Bilateral Advance Pricing Arrangement Manual (OECD, 2022[7]) which is intended as a guide for streamlining the Bilateral APA process to facilitate a cooperative and collaborative process. In addition, the Manual on the Handling of Multilateral Mutual Agreement Procedures and Advance Pricing Arrangements: Enhancing Tax Certainty (OECD, 2023[5]) offers guidance to tax administrations and taxpayers on Multilateral APAs from both legal and procedural perspectives.
Co-operative compliance programmes
Over the last few years, there has been an increasing focus on the use of co-operative arrangements to manage compliance and enhance tax certainty. These programmes often involve a more transparent relationship between tax administrations and taxpayers, and can involve more proactive approaches to resolving material tax risks. The concept of co‑operative compliance has been the subject of several OECD reports, most recently Co‑operative Tax Compliance: Building Better Tax Control Frameworks (OECD, 2016[8]).
As the operation of a co‑operative compliance programme is resource intensive due to the high level of engagement between tax administration officials and taxpayers, traditionally those programmes were reserved for large companies, and close to three-quarters of administrations reported having such programmes for large taxpayers. However, technological advances in risk assessment processes have led to a number of administrations reporting the application of this concept to other taxpayer groups, such as HNWI taxpayers (see Table 8.6.).
Percentage of administrations that have such approaches
Source: ADB, CIAT, IOTA, IMF, OECD, International Survey on Revenue Administration, Table A.107 Cooperative compliance approaches, http://isoradata.org (accessed on 1 October 2025).
The NTA Japan has introduced initiatives to maintain and improve tax compliance for large enterprises, focusing on co-operative compliance approaches.
One of the main initiatives is that the NTA checks the status of large corporations’ corporate governance related to tax matters. Senior officials from Regional Taxation Bureaus of the NTA then discuss with the corporate executives and present them with effective case examples to help them improve tax corporate governance in their own organisations.
With this action, the NTA will be able to take large corporations’ tax corporate governance status into account when evaluating their tax risks. This enables the NTA to more effectively utilise its limited human resources to address high risk areas. From a business perspective, they will be able to reduce risks such as the risk of an inaccurate or incorrect tax processing, and eventually, the risk of errors being identified during tax examinations.
In addition, on its website the NTA provides two types of check sheets: “Check sheet for tax returns,” and “Check sheet for tax items requiring special attention at large enterprises.” The former is expected to be used as a voluntary self-inspection by taxpayers of their tax return ahead of submission, and the latter is expected to be used to check if there is any failure/ omission in the account settlement adjustments or tax declaration adjustments before creating a tax return. Through this process, errors in final returns can be prevented, which ultimately reduces the risk of errors being detected during tax examinations.
Source: Japan (2025).
International Compliance Assurance Programme
The International Compliance Assurance Programme (ICAP) is a voluntary programme for a multilateral co-operative risk assessment and assurance process. It is designed to provide multinational enterprise groups (MNE groups) with increased tax certainty with respect to certain of their activities and transactions as long as they are willing to engage actively, openly and in a fully transparent manner. ICAP does not provide an MNE group with the legal certainty that may be achieved, for example, through an APA. However, it does give assurance when tax administrations participating in an MNE group’s risk assessment consider covered risks to be low risk.1 (OECD, 2021[9])
Joint audits
Another tool that can assist in preventing disputes is a joint audit where officials from two or more administrations join to form a single audit team which will examine issues or transactions of taxpayer(s) with cross-border business activities and in which the jurisdictions have a common or complementary interest. By collaborating it may be possible for the participating tax administrations to detect and address differences or potential disputes at an early stage. (OECD, 2019[10])
References
[3] OECD (2025), Dispute resolution in cross-border taxation, https://www.oecd.org/en/topics/dispute-resolution-in-cross-border-taxation.html (accessed on 1 October 2025).
[6] OECD (2024), Tax Administration 2024: Comparative Information on OECD and other Advanced and Emerging Economies, OECD Publishing, Paris, https://doi.org/10.1787/2d5fba9c-en.
[5] OECD (2023), Manual on the Handling of Multilateral Mutual Agreement Procedures and Advance Pricing Arrangements: Enhancing Tax Certainty, OECD Forum on Tax Administration, OECD Publishing, Paris, https://doi.org/10.1787/f0cad7f3-en.
[7] OECD (2022), Bilateral Advance Pricing Arrangement Manual, OECD Forum on Tax Administration, OECD Publishing, Paris, https://doi.org/10.1787/4aa570e1-en.
[9] OECD (2021), International Compliance Assurance Programme: Handbook for tax administrations and MNE, OECD Publishing, Paris, https://doi.org/10.1787/a44d51e2-en.
[10] OECD (2019), Joint Audit 2019 – Enhancing Tax Co-operation and Improving Tax Certainty: Forum on Tax Administration, OECD Publishing, Paris, https://doi.org/10.1787/17bfa30d-en.
[1] OECD (2017), Tax Administration 2017: Comparative Information on OECD and Other Advanced and Emerging Economies, OECD Publishing, Paris, https://doi.org/10.1787/tax_admin-2017-en.
[8] OECD (2016), Co-operative Tax Compliance: Building Better Tax Control Frameworks, OECD Publishing, Paris, https://doi.org/10.1787/9789264253384-en.
[2] OECD (2015), Making Dispute Resolution Mechanisms More Effective, Action 14 - 2015 Final Report, OECD/G20 Base Erosion and Profit Shifting Project, OECD Publishing, Paris, https://doi.org/10.1787/9789264241633-en.
[4] OECD (2007), Manual on Effective Mutual Agreement Procedures (MEMAP), OECD, Paris, https://doi.org/10.1787/2bb3ab55-en.
← 1. See https://www.oecd.org/en/about/programmes/icap.html for more information (accessed on 1 October 2025).