EIM31707 - The general rule for employees’ expenses: dealing with expenses: how to resolve a dispute: years for which assessments have become final and conclusive

Where an assessment for any year has become final and conclusive the only way that a deduction can be permitted is by a claim under Section 33 TMA 1970.

This is a claim that can be made by any person who has been overcharged in an assessment by reason of some error or mistake in a return. An error or mistake can include an omission from a return, such as forgetting to include a deductible expense.

Guidance on the time limit within which an error or mistake relief claim must be made, together with guidance on how to deal with a claim is at SACM12000.