How far back can HMRC go to recover unpaid tax?

HMRC will go further back over your tax affairs, the more serious they decide your case is.

If they suspect deliberate tax evasion, they can investigate as far back as 20 years. In Code of Practice 9 cases, you always have to consider the previous 20 years when declaring all irregularities. Of course, these may not necessarily go back 20 years, but it is the period to be considered in the course of the preparation of the report.

In mainstream tax enquiries where suspected fraud is not in question, the rules about discovery assessments are still complicated, but basically HMRC will try to recover tax as far back as it is due.

Each individual case is different. A normal four-year period can be extended to six years or as above up to 20 years for more serious tax evasion.