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HMRC internal manual

Business Income Manual

Averaging: giving effect to a claim

Sch1B Para3 Taxes Management Act 1970

Claims for averaging are given effect in, or by amendment of, the return of the later year.

Averaging does not affect the amount of tax due for the earlier year(s) and those self-assessments are not amended.

The tax effect of averaging profits is taken into account in the later year.  That tax effect can be positive or negative. 

Examples of how this works are at BIM84210 onwards.  

Where this generates a repayment see BIM84165.