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HMRC internal manual

Stamp Duty Land Tax Manual

Scope: What is chargeable: Contract and conveyance: General FA03/S44

In the vast majority of cases Stamp Duty Land Tax (SDLT) will arise on completion.

However a charge to SDLT will arise where a contract governing a land transaction is substantially performed before it is formally completed.

Whether or not a contract has been substantially performed is a question of fact.

SDLTM07700+ provides further guidance on the question of when substantial performance takes place.