The introduction of Pillar 2 marks one of the most significant changes to the international corporate tax landscape in decades.
Designed under the OECD’s Base Erosion and Profit Shifting (BEPS) framework, Pillar 2 aims to ensure that large multinational enterprises (MNEs) pay a minimum effective tax rate of 15% in each jurisdiction in which they operate.
While the rules are complex, the immediate priority for affected groups is clear: the first Pillar 2 filing deadline of 30 June 2026 is approaching, and preparation is essential.
Who Pillar 2 applies to and why it matters
Pillar 2 generally applies to multinational groups with consolidated annual revenues exceeding €750 million in at least two of the previous four accounting periods. This threshold aligns with country-by-country reporting requirements, meaning many large groups will already be familiar with some of the underlying data points but Pillar 2 goes significantly further in scope and complexity.
A common misconception is that Pillar 2 only affects groups that expect to pay additional tax. In reality, the compliance obligation exists regardless of whether a top-up tax liability arises. Even where a group’s effective tax rate in a jurisdiction exceeds the 15% minimum, or where an exemption applies, a filing is still required. This makes Pillar 2 not just a tax calculation exercise, but a substantial reporting regime in its own right.
The rules introduce several mechanisms, including the Income Inclusion Rule (IIR) and the Undertaxed Profits Rule (UTPR), which collectively ensure that any shortfall in tax is captured and allocated appropriately across jurisdictions. For many groups, this will require a level of data collection and analysis that goes beyond existing financial reporting systems.
Implications and compliance challenges
The tax implications of Pillar 2 extend beyond simply calculating whether additional tax is due. At its core, the regime requires groups to compute an effective tax rate on a jurisdiction-by-jurisdiction basis, using a bespoke definition of income and covered taxes. This often differs from both local statutory accounts and existing tax computations, creating a need for reconciliation and adjustment processes.
One of the primary challenges is data availability. Many organisations do not currently capture the granular information required to perform Pillar 2 calculations, particularly where operations span multiple territories with differing accounting standards and tax regimes. As a result, finance teams may need to implement new systems or adapt existing ones to ensure compliance.
In addition, the interaction between Pillar 2 and existing tax incentives, such as R&D credits or capital allowances, can produce unexpected outcomes. Incentives that reduce the effective tax rate below 15% may trigger a top-up tax, effectively neutralising their benefit. This has prompted many groups to reassess the value of such incentives and consider whether structural changes are required.
Deferred tax accounting is another area of complexity. Pillar 2 introduces its own rules for recognising and measuring deferred taxes, which may not align with traditional accounting standards. This adds another layer of technical difficulty, particularly for groups with significant temporary differences.
Even in cases where no additional tax is payable, the requirement to prepare and submit a Pillar 2 return means that groups must still undertake the full calculation process. This includes documenting assumptions, maintaining audit trails, and ensuring that the figures reported are consistent with financial statements and other regulatory filings.
The 30 June 2026 deadline
The first Pillar 2 filing deadline of 30 June 2026 is rapidly approaching and given the scale of the work involved, it is vital to be prepared. For many groups, this will be the first time they are required to compile and report the necessary information, making the initial compliance cycle particularly demanding.
Hillier Hopkins is keen to ensure that clients are fully aware of this deadline and the steps required to meet it. Early engagement allows time to assess whether a group falls within scope, identify data gaps, and design appropriate processes for compliance. It also provides an opportunity to model potential tax exposures and consider strategic responses where necessary.
Importantly, the first filing will set a precedent for future years. Establishing robust systems and controls now will not only facilitate compliance in 2026 but also reduce the ongoing administrative burden in subsequent periods. Conversely, leaving preparation too late increases the risk of errors, inefficiencies, and potential scrutiny from tax authorities.
Groups should also be mindful of the need for coordination across jurisdictions. Pillar 2 is a global regime, and consistent application of the rules is essential. This may involve collaboration between local finance teams, central tax functions, and external advisers to ensure alignment and accuracy.
How Hillier Hopkins can help
Given the complexity and far-reaching implications of Pillar 2, many organisations are seeking external support to navigate the new requirements. Hillier Hopkins has been asked by clients to assist in assessing the impact of the rules, implementing compliance frameworks, and preparing for the first filing.
Support can range from high-level impact assessments to detailed calculation modelling and assistance with data collection processes. For groups with limited internal resources or experience in this area, having expert guidance can significantly reduce the risk of non-compliance and provide confidence in the figures reported.
As the 30 June 2026 deadline approaches, the focus should be on readiness. Understanding the rules, identifying obligations, and putting the necessary systems in place will be critical to a smooth transition into the Pillar 2 regime.
