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HMRC internal manual

Debt Management and Banking Manual

Interest: handling interest objections and enquiries: DTO action: interest unaffected by HMRC mistake or unreasonable delay but is pressed

Local offices should thoroughly review each interest objection and fully explain to their customer why the interest charge is correct. You should do this only once.

If your customer won’t accept your decision, you should send the case to the Interest Review Unit (IRU) for a further review.

To get help on how to do this, refer to the guidance on the Interest Review Unit (IRU) intranet page.