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HMRC internal manual

Debt Management and Banking Manual

Debt and return pursuit: PAYE: employer or contractor has lost their records: employer’s records can not be reconstructed

You should issue a P101 estimate based on previous payments and proceed to enforce that amount.

If, however, the loss covers a complete tax year and no payments have been made, you should liaise with COps to decide on the next action, which may be to complete a ‘nil’ pro-forma return (P35/P14s).