In the absence of any specific provision to the contrary, under self-assessment the normal rule is that claims by individuals, trustees and companies are to be made within four years from the end of the tax year or chargeable period to which they relate (TMA 1970, s. 43(1) and FA 1998, Sch. 18, para. 55).
In certain cases, HMRC may permit an extension of the strict time limit in relation to certain elections and claims.
Post-cessation expenses relieved against gains
First anniversary of the 31 January following the end of the tax year for which relief is claimed