Enquiry - notice out of time letter

HMRC must send a formal notice if it intends to start an enquiry into a self-assessment tax return. It has a limited time to do this. Before responding to any questions asked by HMRC check that the enquiry notice has been issued in time. If not advise HMRC that it is out of time.

Deadlines

HMRC can begin an enquiry into a self-assessment personal or company tax return by issuing a notice in writing that is received by the person or company within the so-called enquiry window. If it is invalid the enquiry cannot proceed. 

The enquiry window deadlines are:

Personal tax returns

• for a tax return received on or before the normal filing deadline (31 January following the end of the tax year to which the return relates) the following 31 January. For example, for a return for 2022/23 the deadline is 31 January 2025
• for a return to which the normal filing deadline applies is received by HMRC after the normal filing deadline, twelve months from the date the tax return is received. So for a 2022/23 return received by HMRC on 20 June 2024, the enquiry window ends on 20 June 2025
• for a return submitted but not requested by HMRC (a voluntary return) and received before the normal filing deadline, the enquiry window closes twelve months from the date the return is received
• for a return where the filing deadline is later than the normal deadline, i.e. because HMRC has issued the notice requiring the return late, the enquiry window closes at the end of the quarter day next following the first anniversary of the day on which the return was made.

Amended personal returns

You are allowed to amend a tax return up to twelve months from its filing date, whether that’s the normal filing date or later because HMRC requested the return late. A different enquiry window to applies to the amendment.

For example, if 2022/23 HMRC issued a notice to file after 31 October 2023 the normal filing date of 31 January 2024 would not apply. Instead the filing date would be three months from the date the notice to file was issued (not when it was received). For example, if this date is 1 November 2023 the filing date for the purposes of amending the return is 1 February 2024. A taxpayer can make an amendment to their return up to 1 February 2025.

The amendment does not change the enquiry period for the return, which is explained above.

There is however a separate enquiry window for the amendment. The enquiry period for the amendment is up to the quarter day next, following the first anniversary of the date that the amendment was made.

The quarter days are 31 January, 30 April, 31 July and 31 October.

Company tax returns

If the notice arrives after the enquiry window has ended use our Enquiry - Notice Out of Time Letter to inform HMRC.

Note. If HMRC received the return after 31 January, it has “up to and including the quarter day next following the first anniversary of the day on which the return was delivered…” (s.9A(s)(b) of the Taxes Management Act 1970) within which to issue the notice of enquiry.