Registration for Pillar 2 top-up taxes in the UK

HMRC has published information having the force of law (tertiary legislation) regarding the process for groups with consolidated group revenues of €750m to register in the UK for Pillar 2 top-up taxes. Groups must register within six months of the end of the first accounting period in which they fall within the scope of the rules. The information has been published in Notice 1 "Pillar 2 top-up taxes registration" and supporting information.

Who needs to register?

Any group (which confusingly includes a single entity) with at least one entity located in the UK and which has consolidated group annual revenues of €750m or more in two of the last four accounting periods must register in the UK for Pillar 2. Registration must be via the online service to register and report for Pillar 2 top-up taxes in the UK (and this requirement has the force of law).

It is the filing member for the group who must register. This is the ultimate parent entity (UPE) by default, whether or not they are UK resident, but the UPE can nominate another group member as the filing entity.

The filing member must provide information indicated in Notice 1 (the list has the force of law), which includes:

• Names and addresses of UPE and filing member, together with various contact details
• Company registration number and unique taxpayer reference where either UPE or filing member is in the UK
• Information regarding accounting periods
• Details of whether the group is only located in the UK or is located in the UK and other jurisdictions.

Any changes to the filing member or registration details more generally must be reported online within six months of the relevant change.

If the relevant group consists only of UK entities, then registration is only for the domestic top-up tax. For groups with both UK and non-UK members, registration is for both the UK domestic top-up tax and the multinational top-up tax.

What is the registration deadline?

Registration via the online portal must be completed within six months of the end of the first accounting period starting on or after 31 December 2023. It is necessary to register even if there is no top-up taxes to pay.

Once a group is registered, the first return will be due no later than:

• 30 June 2026, if the first accounting period reported ended on or before 31 December 2024
• 18 months after the last day of the relevant accounting period, for accounting periods ending after 31 December 2024.