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HMRC internal manual

Enquiry Manual

Working the Enquiry: Taxpayer Amendments



A taxpayer can amend his or her return at any time up to the end of the period of 12 months from the fixed filing date and have those amendments reflected in the self assessment.

The taxpayer’s right to amend the self assessment is changed if an enquiry is opened into the return. In that case any amendment that the taxpayer makes can only be given effect at the end of the enquiry EM3835. Where a partial closure notice (PCN) is issued you should consider allowing any taxpayer amendments that relate to the matter being settled by the PCN. Otherwise the amendment will only take effect when the enquiry is completed and a Final Closure Notice is issued.

Any amendments to the self assessment which are received during the course of an enquiry should therefore not be processed until such time that the enquiry into that matter is concluded by the issue of either a partial or final closure notice, or settled via contract settlement. Entering the enquiry start date on the computer record inhibits access to ‘Amend Return’ or ‘Create Return Charge’.

Any amendments received while an enquiry is in progress should be referred immediately to the case owner for that enquiry.

The amendment will indicate that the return submitted was incorrect. If there is additional tax due and it can be shown that the taxpayer was

  • negligent, or
  • careless, for periods beginning on or after 1 April 2008 where the filing date of the return was on or after 1 April 2009, see CH81140

then penalties may be chargeable. In some cases the early disclosure may lead to the complete abatement (or for instances within the second bullet above, complete reduction, see CH82400+) of any penalty. You should consult your compliance manager if you consider there may have been neglect or carelessness.

If you have concluded your enquiry before the taxpayer’s 12 months for amending have expired they can amend their return further at a later date, providing they are still within the 12 months.

If a taxpayer tells you of an error in the return outside the time limit for a taxpayer amendment then you should consider

  • if tax has been over assessed, whether the conditions for a repayment claim are met, either under specific claims provisions or under the error or mistake provisions at Section 33, or
  • if tax has been under assessed, whether the conditions for a discovery assessment are met EM3250.