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HMRC internal manual

Enquiry Manual

Reopening Earlier Years: Discovery in Pre-SA Years: Further Assessments

The guidance below applies to income tax and CGT assessments for pre-SA periods only.

TMA70/S29(3) (Old)

The first assessment in point of time made in respect of a particular source of income for any year is referred to as a main assessment. A further assessment on the same source for the same year may be made, within the appropriate time limit, if an enquiry officer discovers that an assessment is or has become insufficient or that any relief which has been given is or has become excessive. Additionally where, after an assessment has been made or a decision taken that an assessment is not required, an enquiry officer discovers that any taxable profits have not been assessed, he may make an assessment in the amount he considers ought to be charged.

A further assessment should not normally be made where the relevant main assessment is still under appeal and has not been finally determined. Where, exceptionally, there is a large margin between the tax assessed and that apparently due and an adequate payment on account (based upon the tax apparently due) cannot be obtained informally, see EM3290.