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HMRC internal manual

Debt Management and Banking Manual

Interest: contents

Interest is charged to provide a measure of fairness between those customers who pay on time and those, who for whatever reason, pay late. Also interest is used to compensate the Exchequer for the loss of the use of the funds.

The legislation covering the charging of interest has been introduced over a long period of time and covers many charges and duty types. The rules for calculating interest often differ across the range of charges, duties and the various customer groups; for example employers, self employed and companies.