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HMRC internal manual

Self Assessment Manual

Amend payment: claim to adjust payments on account: incorrect adjustments and errors

Adjustment and re-allocation

Where an adjustment reduces a payment on account below the amount paid, a re-allocation is triggered and the record may become overpaid.

A subsequent re-allocation of an overpaid amount against a charge for which the due date has passed may cause interest and repayment supplement (RPS) to be calculated and included on the taxpayer record.

Advice about correcting errors

Unless you are clear about the interest and RPS consequences, you should always refer to your Manager before attempting to correct these cases. Your Manager can contact the BusinessUserSupport (SA) mailbox for information about what transactions to use and in what sequence.

If you come across a case where inappropriate amounts of interest and / or RPS are included on the taxpayer’s record, refer to subject ‘Payment Allocation and Transfer’ (SAM80050) and then the Debt Management and Banking Manual (DMBM). Again you should seek the assistance of your Manager and where necessary, the BusinessUserSupport(SA), mailbox if you are unsure how to proceed.