Pillar Two has been in force across the European Union for financial years opened on or after 31 December 2023, and the groups it catches are discovering that the hard part is not the 15% rate. It is assembling, jurisdiction by jurisdiction, figures that were never produced at that granularity before.

The computation is jurisdictional, not per entity. Qualified income and adjusted covered taxes are aggregated across every constituent entity in a country — a loss in one offsets a profit in another — and the effective tax rate falls out of that aggregate. A group with one heavily taxed entity and one lightly taxed entity in the same country may well be compliant; the same two entities in different countries may not.

The substance-based income exclusion is what separates a real operation from a booking entity. It removes from the base a percentage of eligible payroll costs and of the carrying value of tangible assets. Those percentages are on a declining transitional schedule — 9.4% and 7.4% for 2026, down to 5% and 5% from 2033 — so a rate copied from a 2023 memo will produce the wrong answer.

Two things catch groups out. The first is the de minimis exclusion, which applies on a three-year average rather than a single year: a jurisdiction that looks exempt this year may not be once the two previous ones are included. The second is the ownership chain. The top-up tax is allocated between entities pro rata of their qualified income, and the parent's share of it depends on its effective interest — the product of the holding percentages down the chain, not the direct percentage.

None of this can be assembled from a consolidation package alone. It needs the group's legal structure, its jurisdictions and its holding percentages held as data, not as a slide.

Methodology

Aggregate qualified income and adjusted covered taxes by jurisdiction, not by entity
Compute the effective tax rate on that aggregate, before any loss carry-forward
Apply the substance-based exclusion at the transitional rates in force for the year
Check the de minimis thresholds on the three-year average of revenue and income
Allocate any top-up tax pro rata of positive qualified income, then apply the effective interest

Key Takeaways

1.The computation is jurisdictional: a loss in one entity offsets a profit in another, in the same country
2.The substance rates are on a dated schedule — a rate from an old memo gives the wrong answer
3.De minimis is assessed on three years, not on the current one
4.The parent's share depends on the effective interest, not on the direct holding percentage
5.It is a simulation for decision-making; the return remains the work of the group's tax counsel