BIM86029 - TMIA - Elections: Late Elections
HMRC expect individuals to make claims and elections within statutory filing deadlines. However, a claim or election may be included in a return that is delivered after the time limit for making the claim or election has passed.
Individuals can make a return including elections under sections 783AL and 783BJ (for full relief not to be given), or 783AM and 783BK (for partial relief to be given), to give themselves the benefit of the allowance within the general four year time limit for making claims.
More details regarding claims can be found in the Self-Assessment Claims Manual guidance at SACM10035.