Published June 24, 2026 in Issue 2, 2026
Louise Kelly, Tax Partner, Deloitte Ireland LLP
Dylan Reilly, Tax Manager, Deloitte Ireland LLP
The OECD Forum on Tax Administration has released a new document, the Global Minimum Tax Implementation Toolkit, offering practical guidance to help jurisdictions apply the Pillar Two global minimum tax (GMT) rules in a consistent and coordinated manner. As noted in the document, the Toolkit is intended to support tax authorities as they implement the GloBE framework and manage the related administrative demands. The Toolkit is organised into five modules covering scoping, legislative design, administration, compliance and information exchange.
Module 1: Assessing in-scope MNE groups and revenue
Jurisdictions are encouraged to use country-by-country (CbC) reports as the starting point for identifying in‑scope groups, while recognising limitations such as currency translation differences. A simplified approach for estimating potential top‑up tax revenue is outlined.
Module 2: Legal implementation
Three implementation methods are described:
Each approach has trade‑offs between consistency, flexibility and administrative burden. The Toolkit also recommends including an interpretative clause to ensure that domestic rules align with the Model Rules.
Module 3: Organising and planning for implementation of the GMT
Tax authorities are advised to develop a comprehensive implementation plan covering governance, staffing, IT systems and budget. The Toolkit stresses the importance of training specialist staff and sets out IT best practices, including support for the GIR XML schema (requiring local filing of the global minimum tax information return (GIR) in the agreed XML format).
Module 4. Framework on compliance procedures
Best practices include:
Module 5. Exchange of information
The Toolkit explains how the GIR Multilateral Competent Authority Agreement enables automatic exchange of GIR data, allowing groups to file once and have information disseminated to relevant jurisdictions. Tax authorities are encouraged to activate exchange relationships early and implement full validation rules from the outset.
Next steps
The first GIR filings – for groups with a 31 December 2024 year‑end – are due by 30 June 2026. The OECD notes that jurisdictions continue to collaborate to address coordination challenges, including delays in portal readiness.
The OECD Inclusive Framework (IF) plans to launch peer-reviews of countries’ domestic minimum‑tax rules by the end of 2026 to verify consistency with the Pillar Two GloBE standards. Alongside this, the IF is preparing updates to the GloBE information return to integrate the “side‑by‑side” provisions. The OECD Secretariat is also working to broaden the network of jurisdictions participating in the Multilateral Competent Authority Agreement for GloBE data exchange, with the first exchanges expected in December 2026.
The OECD Secretary‑General has also delivered the latest tax update to G20 Finance Ministers and central bank governors, highlighting progress on implementing the global minimum tax, improvements in tax transparency and continued efforts to support developing countries.
US Treasury officials have indicated that their primary focus in the ongoing OECD Pillar Two work is ensuring smooth global adoption of the side‑by‑side (SBS) framework. Their aim is to provide jurisdictions with clear, workable guidance so they can implement the SBS provisions without facing technical uncertainties or gaps.
The Treasury is currently addressing several complex issues, including the interaction between existing US rules and the SBS mechanism, the treatment of transition‑year starting points, intragroup financing considerations and necessary updates to the GloBE information return.
Brazil has formally asked the OECD to acknowledge the country as eligible for the Pillar Two side‑by‑side (SBS) regime. According to officials from the Brazilian Federal Revenue Service, a response from the OECD is anticipated around mid‑year. The request was publicly confirmed on 23 March by the head of the agency’s International Relations Office.
The SBS approach is viewed as particularly beneficial for Brazilian multinationals. Brazil is the first jurisdiction – other than the United States – to submit an official application for recognition under this mechanism. At present, the safe harbour applies exclusively to US‑parented groups.
Under the SBS rules companies headquartered in qualifying jurisdictions are exempt from two central elements of Pillar Two: the income inclusion rule (IIR) and the undertaxed profits rule. However, the regime does not remove the requirement to apply a qualified domestic minimum top‑up tax (QDMTT). As a result, Brazil’s own QDMTT (the Adicional da CSLL) would continue to apply to Brazilian‑headed multinational groups.
The Brazilian tax authority also noted that it is still uncertain whether the OECD will request legislative adjustments in Brazil as a condition for granting recognition. For the moment, changes to Brazil’s existing controlled foreign company rules (Tributação em Bases Universais) appear less likely. No short‑term amendments are expected, and the introduction of an IIR in Brazil is not currently being considered.
Curaçao’s Ministry of Finance has announced a shift in its Pillar Two policy direction, confirming that the jurisdiction will not introduce a qualified domestic minimum top‑up tax (QDMTT) at this stage. The decision reflects concerns that a domestic minimum tax could undermine the island’s appeal to investors, particularly US‑based multinational groups.
Instead of adopting a QDMTT, Curaçao intends to apply the income inclusion rule with retroactive effect from 1 January 2025. The implementation of the undertaxed profits rule will be deferred, as the Government expects limited practical benefit and anticipates significant challenges in administering and enforcing the rule.
On 3 April 2026 the Belgian tax authorities announced another extension of the first‑year filing deadlines for both the qualified domestic minimum top‑up tax (QDMTT) return and the income inclusion rule (IIR) return. Both filings may now be submitted up to 30 September 2026.
QDMTT return
IIR return
GloBE information return
The GIR deadline remains unchanged:
Implications for multinational groups
The extended deadlines for the QDMTT and IIR filings give taxpayers additional time to prepare their first Pillar Two submissions. At present, Belgium’s electronic filing platform is not yet operational, and the finalised forms and technical specifications have not been released (although draft versions are available). Further procedural guidance will be issued by the Belgian authorities in due course.
Despite the extensions, taxpayers should continue progressing their Pillar Two compliance work. Importantly, the GIR deadline has not been postponed. For calendar‑year groups, the GIR must still be filed by 30 June 2026, meaning that groups need to ensure that data for Belgian constituent entities is complete and ready for reporting.
The Australian Taxation Office (ATO) has released an updated set of materials explaining how Australia’s global and domestic minimum tax (DMT) rules operate under Pillar Two. The expanded guidance, published on 12 March 2026, provides multinational enterprise (MNE) groups with additional clarity on scope, entity classification and compliance expectations.
A major feature of the update is a more detailed explanation of how Pillar Two interacts with Australia’s tax consolidation regime. The ATO now provides guidance on identifying constituent entities within consolidated groups, allocating top‑up tax, handling intra‑group eliminations, and addressing issues such as misaligned fiscal years and restatements of prior‑period financial information. The guidance also expands on the treatment of more complex structures – including joint arrangements, permanent establishments, flow‑through entities and dual‑resident entities – and clarifies how income, taxes and jurisdictional effective tax rates (ETRs) should be calculated.
The ATO also discusses the timing and impact of foreign income tax offsets, including how post‑filing adjustments and amended foreign assessments may influence GloBE ETR outcomes and potential top‑up tax liabilities. The update incorporates the OECD’s safe harbour framework and outlines new filing obligations, including the GloBE information return and separate income inclusion rule, undertaxed profits rule and DMT returns.
The ATO stresses that MNE groups should prioritise data readiness, governance processes and system capability before the first filing cycle.
The Maltese Government has issued an amendment to Subsidiary Legislation 123.212 – the European Union Global Minimum Level of Taxation for Multinational Enterprise Groups and Large‑Scale Domestic Groups. The amendment confirms that constituent entities located in Malta will not be required to submit a top‑up tax information return to the Commissioner for Tax and Customs.
In addition, where relevant, Maltese constituent entities will also be relieved of the obligation to notify the Commissioner of the identity and jurisdiction of the entity responsible for filing the top‑up tax information return on behalf of the group.
These changes apply to qualifying multinational enterprise groups and large‑scale domestic groups for financial years beginning on or after 31 December 2023 (i.e. the 2024 financial year).
The full text of the European Union Global Minimum Level of Taxation for Multinational Enterprise Groups and Large‑Scale Domestic Groups (Amendment) Regulations, 2026 – introduced through Legal Notice 48 of 2026 on 20 February 2026 – is available in the Official Gazette.
The OECD has continued to expand the list of jurisdictions participating in the Multilateral Competent Authority Agreement on Automatic Exchange of Information on Income Derived Through Digital Platforms (DPI MCAA). According to the OECD’s most recent published information, Austria and France signed the DPI MCAA on 17 March 2026 and 30 March 2026, respectively. This brings the total number of signatories to 35.
The purpose of the DPI MCAA remains unchanged from the OECD’s original 10 November 2022 announcement: the agreement enables participating jurisdictions to automatically exchange information collected by digital platform operators regarding income earned by platform sellers in the sharing economy and the gig economy and from the sale of goods. The annual exchange of this data is intended to support both tax administrations and taxpayers in ensuring the accurate and efficient taxation of platform‑derived income.
The OECD released its latest tax report on 16 April, outlining recent developments and emerging trends across several core areas: implementation of the global minimum tax and the broader BEPS agenda; the future international tax framework in a digitalised economy; expanding tax transparency initiatives; tax policy and economic growth; global mobility; and tax administration and certainty.
The report notes that Pillar Two implementation continues to advance worldwide, supported by new simplifications such as safe harbours and additional administrative guidance. Many jurisdictions have already enacted their rules or are close to doing so.
Momentum is also increasing around multilateral solutions for taxing the digital economy, with further changes expected as discussions progress. The report highlights the growing scope of international reporting frameworks, including the extension of transparency rules to real estate holdings and to crypto‑assets under the Crypto-Asset Reporting Framework, which may lead to higher compliance obligations and greater scrutiny for taxpayers.
The OECD also draws attention to the rising prevalence of remote work and cross‑border mobility, which can heighten permanent establishment exposure and create new compliance challenges. In parallel, tax administrations are making greater use of digital tools, data analytics and cross‑jurisdictional information sharing, resulting in more sophisticated and coordinated audit activity.
Gerassimos Thomas, Director‑General for Taxation and Customs Union at the European Commission, has confirmed that the Commission remains deeply engaged in international tax discussions, particularly those concerning the taxation of the digital economy. He noted that both the Commission and EU Member States have long been preparing for either the Pillar One Multilateral Convention or, if necessary, domestic alternatives. Thomas emphasised that progress now depends on the OECD, calling for negotiations to be relaunched.
In terms of the Commission’s own agenda, Thomas highlighted several forthcoming initiatives:
Thomas outlined these priorities on 17 March 2026 during his opening remarks on the second day of the EU Tax Symposium in Brussels.
From a tax perspective, the European Commission’s EU Inc. proposal introduces a harmonised framework for EU‑wide employee stock option plans (EU‑ESO). Chapter VIII (Articles 78 and 79) sets out the tax treatment of warrants issued under these plans:
The proposal will now be examined by the European Parliament and the Council, with the aim of reaching agreement by the end of 2026. Once adopted, the Regulation would apply 12 months after entry into force, allowing time for Member States and companies to prepare.
Belgium has enacted new legislation introducing a capital gains tax on disposals of shares and crypto‑assets. The tax applies at progressive rates ranging from 1.25% to 10%, depending on the circumstances. The reform also brings in a 10% withholding tax on certain financial instruments and insurance‑based investment products.
The Indian Central Board of Direct Taxes (CBDT) has issued a notification confirming that the general anti‑avoidance rules (GAAR) will not apply to income arising from the transfer of investments acquired before 1 April 2017 — the “grandfathered” shares. The amendment and accompanying explanatory statement clarify that capital gains on disposals of such pre‑2017 investments fall outside the scope of the GAAR. This clarification follows the Supreme Court’s observations in its decision in Authority of Advance Rulings (Income Tax) and Others v Tiger Global International II Holdings and Others (Civil Appeal Nos 262, 263 and 264 of 2026), where the court noted that capital gains on grandfathered shares could still be subject to GAAR if they formed part of a broader abusive arrangement.
This decision marked a major shift in India’s approach to treaty eligibility, substance and the GAAR. Key findings from the judgment include:
By issuing this notification the CBDT has effectively relaxed the stricter implications of the ruling and reassured foreign investors that historical structures will not face GAAR scrutiny, even as the Tiger Global judgment continues to shape India’s broader substance‑over‑form and anti‑avoidance approach.
The Dutch tax administration has released new guidance explaining how the concept of a “treaty permanent establishment” (verdragsvaste inrichting) should be interpreted for the purposes of Article 1.2(1)(a) of the Minimum Tax Act 2024 (Wet minimumbelasting 2024; MTA). Under the statutory definition, a PE qualifies as a treaty PE only where:
The guidance addresses two specific interpretive questions relevant to determining whether PE income satisfies these conditions:
On the first point, the tax administration clarified that it is not enough for the treaty to allocate taxing rights to the PE jurisdiction. The income must also be subject to tax under that jurisdiction’s domestic rules.
On the second point, the tax administration stated that the income must be taxed on a net basis, consistent with the separate‑entity approach embedded in Article 7 of the OECD Model. A gross‑basis withholding tax would not satisfy this requirement. The taxation should also be broadly aligned with how resident taxpayers are taxed in that jurisdiction.
The UK Supreme Court has unanimously found in favour of HMRC in the long‑running capital allowances dispute culminating in Ørsted West of Duddon Sands and Others v Commissioners for His Majesty’s Revenue and Customs [2026] UKSC 12. The taxpayers, who develop and operate offshore windfarms, had incurred substantial expenditure on environmental, geological and other site‑specific studies that were essential for project design and for securing regulatory approvals. HMRC rejected claims for capital allowances on these costs, and the Supreme Court has overturned the earlier Court of Appeal ruling, holding that such studies do not amount to expenditure “on” the provision of the windfarms and therefore fall outside the scope of qualifying capital expenditure. The court did not attempt to define the precise boundary between costs that do and do not relate to the provision of plant but concluded that Ørsted’s development‑stage studies were clearly on the non‑qualifying side of that line. After the Court of Appeal’s earlier decision, HM Treasury had paused its planned consultation on the tax treatment of development expenditure, and an updated consultation is now expected. The Supreme Court’s narrow interpretation, combined with the remaining uncertainty around borderline cases, is likely to prompt closer scrutiny of development‑phase costs on major infrastructure projects and may influence HMRC’s approach more broadly. (See also “Direct Tax Cases Decisions UK Courts” in this issue.)