Assignment
The transfer of the whole of a party's remaining interest in property or a contract to another person. In a lease, an assignment transfers all of the tenant's remaining interest for the rest of the term, as distinct from a sub-lease.
Independent editorial summary — not the official statute text. Read the official version on legislation.gov.uk.
HMRC's guidance on lease premiums draws the line precisely, because the tax treatment turns on which side of it a transaction falls: 'It is only an assignment of the lease if all the lessee's interest in the lease for the whole of the rest of the term is transferred.' Anything less than that — even a shortfall of a single day — is treated differently in law.
That single-day distinction is not a technicality that HMRC glosses over; it is stated as the actual test: 'Where a transfer purports to be an assignment, but is for a period of less than the remainder of the term, even if only one day less, it is not an assignment but a sub-lease.' A sub-lease leaves the original tenant with a reversionary interest and ongoing obligations to the head landlord, whereas a true assignment hands over the tenant's entire remaining position, which is why the distinction matters well beyond tax law.
Related terms
Official sources
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