SDLTM50260 - Procedure: Completion following Substantial Performance of agreement for lease
If an agreement for the grant of a new lease was substantially performed (notional transaction), a further return will be due on actual completion. In these circumstances the grant is treated as a completely separate transaction (although linked to the notional transaction), overlap relief will be available. As a result, the further return will be a new SDLT1 sent to:-
HM Revenue & Customs Stamp Taxes
and not a letter. However, if the NPV is nil because of the overlap relief, no notification is required and no action need be taken. Please note that application of overlap relief cannot lead to a negative figure, so no refund will be available if the tax calculation on the grant of the lease is less than that paid on substantial performance.