The way in which any errors found in the course of a pre-return check will be dealt with depends on whether or not the errors affect a return that has already been filed. If they do not, the officer will simply offer guidance on how to correct the error to avoid submitting an incorrect return or on paying the correct amount of tax for the period covered by the check.
If a pre-return check shows that a taxpayer has made an error that has led to them paying too much tax, they can:
If the check leads the officer to suspect that tax has not been assessed, or has been under-assessed, or that excessive reliefs have been given, then:
If the officer can raise an assessment, then the information powers contained in Finance Act 2008, Sch. 36 can be used to obtain the information needed to decide on the quantum of the assessment.