This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

International Manual

Double Taxation applications and claims: Repayment claims from non-residents: Giving effect to amendments following an enquiry

When you have sent a closure notice to the claimant you have 30 days from the date of issue of the closure notice to give effect to any amendment made. You do this by either repaying the tax or by making an assessment on the claimant if the claim was excessive and you have already made a repayment.

For full guidance on how to give effect to amendments following an enquiry see INTM331350.