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HMRC internal manual

VAT Flat Rate Scheme

Treatment of Applications: Can HMRC allow a retrospective start date for FRS?

Yes. Regulation 55B(1)(b) of VAT Regulations 1995 allows for a start date that is earlier than the date of application. This is a power which the Commissioners must use reasonably in the circumstances of each case. Your duty as the decision maker is to consider all the relevant facts and not make a decision on the basis of any irrelevant facts. If you do refuse to allow retrospection, you should explain the reason and indicate the main factors you took into account in reaching your decision.

FRS3300 gives guidance on the criteria to be considered when deciding retrospection requests.