Tax arrangements subject to the Mandatory Disclosure Rules (MDR) are arrangements governed by Articles 86a–86o of the Polish Tax Ordinance Act[1]. These provisions require the Head of the National Revenue Administration to be notified of arrangements that display certain prescribed characteristics. Contrary to a common misconception, the reporting obligation does not apply solely to arrangements bordering on aggressive tax planning. Due to the broad statutory definition of a tax arrangement, entirely standard transactions or business structures may also be reportable. The reporting obligation is purely informational and does not, in itself, imply that a particular arrangement is improper. Failure to comply may, however, result in significant 

The Polish MDR provisions implement the EU DAC6 Directive[2]. However, the Polish legislature chose to introduce reporting obligations extending beyond those required by the Directive. This included, among other things, the reporting of domestic tax arrangements and the extension of the material scope of the rules to taxes not covered by DAC6, including value added tax and excise duty.

Previous scope of MDR reporting

To date, the MDR provisions have distinguished between three types of reportable arrangements: tax arrangements, standardised tax arrangements and cross-border tax arrangements. A reporting obligation arose where the relevant arrangement satisfied the applicable statutory criteria and displayed one or more prescribed hallmarks.

In this respect, the Polish MDR framework went significantly beyond the scope required by DAC6. The reporting obligation applied not only to arrangements involving a cross-border element, but also to a broad range of arrangements concerning purely domestic transactions.

In practice, this created a significant risk of over-reporting, particularly due to uncertainty as to whether the statutory conditions for a tax arrangement had been met and the severe penalties for failure to comply. As a result, entities frequently adopted a precautionary approach and reported arrangements even where their reportability was uncertain.

Changes introduced by the amendment to the Polish Tax Ordinance Act

On 19 June 2026, the President of the Republic of Poland signed the Act of 29 May 2026 amending the Polish Tax Ordinance Act and certain other acts[3]. The Act introduces a number of amendments, including significant changes to the MDR framework. This alert discusses selected aspects of the new legislation.

The changes described below will enter into force on 1 October 2026.

End of domestic tax arrangement reporting

From 1 October 2026, only cross-border arrangements will be subject to MDR reporting. The amending legislation removes the category of domestic tax arrangements and the “other specific hallmarks” that went beyond the requirements of DAC6. It also removes general hallmarks that are not provided for under DAC6. For taxpayers operating exclusively on the domestic market, this will, in practice, mean the end of MDR reporting obligations. In addition, value added tax and excise duty will no longer fall within the scope of the MDR provisions, as these taxes have been expressly excluded from the application of the rules.

Simplification of roles: abolition of the separate supporting entity role

The amending legislation abolishes the separate role of the supporting entity. In line with the model established by DAC6, only the promoter and the beneficiary will remain. Activities previously performed by a supporting entity will continue to be relevant, but will now be classified as “supporting activities” performed as part of the promoter’s role. This change narrows the category of persons subject to the reporting obligations and clarifies the rules governing responsibility for making a notification.

Stronger protection of professional secrecy

Promotor obowiązany do zachowania prawnie chronionej tajemnicy zawodowej, a więc adwokat, radca prawny, doradca podatkowy lub rzecznik patentowy, jest zwolniony z obowiązku raportowania. Nowelizacja znosi przy tym dotychczasowe rozróżnienie, obejmując zwolnieniem także schematy standaryzowane, w odniesieniu do których raportowanie było wcześniej wymagane. Na takim promotorze będzie ciążył natomiast obowiązek poinformowania klienta, to jest korzystającego albo innego promotora, o konieczności samodzielnego zgłoszenia schematu Szefowi KAS. Zmiana stanowi realizację stanowiska wyrażonego w wyroku TSUE w sprawie C-694/20 (Orde van Vlaamse Balies) oraz dostosowanie do regulacji dyrektywy DAC8^[4].

MDR-3 to be submitted only once a year and capable of being signed by an authorised representative

The beneficiary will be required to submit information on the use of an arrangement on the MDR-3 form once a year, by the end of the fourth month following the end of the tax year. Entities that are not subject to corporate income tax or personal income tax will be able to submit the information by the end of the fourth month following the end of the calendar year. This represents a relaxation of the existing rules, under which MDR-3 reporting was linked to each tax return covering the relevant reporting period. The form will also be capable of being signed by an authorised representative. Where the exact amount of the tax benefit cannot be determined, it will be permissible to provide an estimated amount.

End of the mandatory internal MDR procedure and penalties for failure to implement it

The obligation to maintain an internal MDR procedure, together with the financial penalty for failing to implement such a procedure, has been repealed. Proceedings concerning a failure to implement an internal MDR procedure that were commenced but not concluded before the new provisions enter into force will be discontinued, as the amended rules are more favourable to the parties concerned.

Summary

For taxpayers and their professional advisers, the amendment to the Polish Tax Ordinance Act primarily represents a significant reduction in the administrative burden. It brings an end to the widespread reporting of domestic arrangements, reduces the number of required filings, introduces a single annual MDR-3 submission, abolishes the mandatory internal MDR procedure and the associated penalties, and strengthens the protection of professional secrecy.

The MDR regime is not being abolished. Instead, it is being refocused on the arrangements required to be reported under EU law, namely cross-border arrangements.

It should nevertheless be remembered that the existing rules will remain in force until 30 September 2026. Domestic tax arrangements for which the reporting obligation arises before that date must therefore be reported under the current rules.

However, the transitional provisions of the amending legislation provide a degree of simplification. Where information concerning a domestic arrangement has been submitted before the amending legislation enters into force, no further information on the use of that arrangement will need to be submitted.

^[1] UAct of 29 August 1997 – the Polish Tax Ordinance Act (consolidated text: Journal of Laws of 2025, item 111, as amended; hereinafter: the “Polish Tax Ordinance Act”).

^[2] Council Directive (EU) 2018/822 of 25 May 2018 amending Directive 2011/16/EU as regards mandatory automatic exchange of information in the field of taxation in relation to reportable cross-border arrangements (OJ EU L 139, 2018, p. 1, as amended; hereinafter: “DAC6”).

^[3] Journal of Laws, item 846; hereinafter: the “amending legislation”.

^[4] Council Directive (EU) 2023/2226 of 17 October 2023 amending Directive 2011/16/EU on administrative cooperation in the field of taxation (OJ EU L, 2023/2226, as amended).