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HMRC internal manual

International Manual

Double Taxation applications and claims: Repayment claims from non-residents: Appeals against amendments following an enquiry

A claimant may appeal against any conclusion stated or amendment made by a closure notice by giving notice in writing within 30 days of the date of issue of the closure notice, or within three months of that date where the closure notice mentions that longer period.

For full guidance on what to do if you receive an appeal against an amendment see INTM331400.