From 6 May 2025, HMRC will no longer confirm a taxpayer’s unique taxpayer reference (UTR) number over the phone. This change applies to individual taxpayers and agents calling on behalf of clients.

Instead, UTR numbers will only be available through HMRC’s digital services via the HMRC app or a personal tax account on GOV.UK. Taxpayers familiar with these services should find their UTR easy to locate, as it is displayed in the account. It also appears on documents such as tax returns, notices to file, and payment reminders.

The move is part of HMRC’s efforts to strengthen data security and prevent personal information from being given out incorrectly. While the department has notified professional bodies about the change, it has not yet updated public guidance on GOV.UK.

HMRC will confirm UTR numbers by post after a series of security checks for those unable to use digital services. This means it could take longer to access the number if it’s lost or hasn’t arrived within the usual 15-day window after registering for self assessment.

The Association of Taxation Technicians has issued an alert, noting that agents will be pointed to where a UTR can be found, or offered postal confirmation where needed.

All taxpayers need a 10-digit UTR to file a self assessment return, so anyone registering or updating records should plan for possible delays under the new system.

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