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HMRC internal manual

Stamp Duty Land Tax Manual

Calculation of Stamp Duty Land Tax (SDLT): Rent: Term includes a part year: Example 1

A lease of non-residential property is granted on 1 July 2015 commencing on that date and ending on 31 October 2018 at a rent of £75,000 per annum. The term of the lease is therefore 3 years and 123 days.

To calculate the net present value (NPV), the annual rental figure of £75,000 is used as the rent for the first three years’ rent and is apportioned to arrive at the rent for the fourth part year (£75,000 x 123/365 = £25,273).

The NPV is £232,146. This can be calculated manually or using the NPV calculator provided on the Gov.Uk website