Stamp Duty Calculation for Leases with Variable Rent and Market Rent Revision

SDLT on a Lease with a Market Rent Review After Four Years

Where a lease includes a later market rent review, SDLT must still be reported and paid on time using the rent that is known and a reasonable estimate for any uncertain rent. For a seven-year lease with a review after year four, the initial calculation includes the actual rent for years one to four, an estimate for year five, and for years six and seven the highest annual rent in the first five years. Once the review is settled, the tenant should amend the return and SDLT is recalculated, with extra tax payable or a refund due if too much was paid.

• SDLT on a lease is partly based on the net present value of the rent over the term, even if some later rent is not yet fixed.
• The first return must use the known rent for years one to four and a reasonable estimate of the reviewed market rent for year five.
• For years six and seven, the calculation uses the highest rent payable in any twelve-month period within the first five years, not simply the estimated year five rent.
• When the rent review is finally determined, the tenant should send an amended return to HMRC Stamp Taxes to correct the SDLT position.
• If the revised figures change the NPV, SDLT is adjusted with credit for tax already paid, and any overpayment may be refunded.
• Good records are important, including the lease terms, review clause, basis of the estimate, and the date the uncertainty is fully resolved.

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SDLT on a lease with a market rent review after four years

This page explains how SDLT is worked out where a lease includes rent that is not fully known at the start because of a later market rent review. The official example deals with a seven-year lease where the rent is reviewed after year four. The key point is that the tenant must file an initial return using what is known and what can reasonably be estimated, and then amend that position once the uncertainty is resolved.

What this rule is about

SDLT on the grant of a lease is charged partly by reference to the net present value, or NPV, of the rent payable over the term. That is straightforward where the rent is fixed from the outset. It is more complicated where some later rent is variable or uncertain.

The official material addresses that problem. It explains how to deal with a lease where the rent for later years depends on a market rent review. At the filing date, some rent is known, some has to be estimated, and some later years depend on identifying the highest rent payable in any twelve-month period in the first five years.

This matters because SDLT is not postponed until every review is settled. A return still has to be filed, and it has to include a sensible calculation based on the rules for uncertain rent. Later, that calculation may need to be corrected.

What the official source says

The source example concerns a lease granted for seven years with a market rent revision after four years.

On the original land transaction return, the NPV must include:

• the known rent for years one to four,
• a reasonable estimate of the market rent for year five, and
• for years six and seven, the highest rent, whether known or estimated, payable for any twelve-month period in the first five years.

Once the rent is determined on review at year four, or at year five if it is not determined sooner, an amended return should be made by letter to HMRC Stamp Taxes. That amended calculation should include:

• the known rent for years one to four,
• the revised rent for year five, using the actual figure if known, or a reconsidered estimate if it is still not determined, and
• a revised calculation for years six and seven using the highest rent payable in any twelve-month period in the first five years, if that changes the result.

SDLT is then charged on the revised NPV. Credit is given for SDLT already paid on the original return. If too much tax was paid originally, a refund is due. The source states that this is done from thirty days after the date all uncertainty is determined.

What this means in practice

The practical effect is that the tenant cannot ignore the rent review just because the reviewed rent is not yet fixed. The initial SDLT return still has to include a best view of the position.

For this type of lease, there are really two stages.

First, at the outset, you calculate the NPV using:

• actual rent where it is already fixed,
• a reasonable estimate where the reviewed rent is not yet known, and
• for the later years, the highest annual rent appearing in the first five years.

Second, once the review outcome becomes known, or can be estimated more accurately, you revisit the calculation. If the revised figure changes the NPV, SDLT is recalculated. Any extra tax becomes payable, or any overpayment can be reclaimed.

The reference to the highest rent in any twelve-month period in the first five years is especially important. For years six and seven in this example, you do not simply carry forward the year five estimate because it was year five. Instead, you identify the highest rent payable in any twelve-month period within years one to five and use that figure for those later years, unless the revised information changes it.

How to analyse it

A sensible way to approach this type of lease is to ask the following questions.

• What rent is fixed and known at the effective date of the transaction?
• Which rent figures are still uncertain because of a review clause?
• What is a reasonable estimate for the first uncertain year?
• Looking at the first five years, what is the highest rent payable in any twelve-month period?
• Does that highest figure need to be used for later years under the uncertain rent rules?
• When the review is settled, does the actual or revised figure alter the highest rent in the first five years?
• If it does, how does that change the NPV and the SDLT due?

In practice, this means keeping a clear record of:

• the lease terms,
• the rent review mechanism,
• the basis for the original estimate, and
• the date on which the uncertainty is finally resolved.

Those details matter because the amended return is not just a formality. It is the mechanism for bringing the SDLT position into line with the actual or revised rent position.

Example

Illustration only. A tenant takes a seven-year lease. The rent is fixed for years one to four, but after year four it moves to market rent. At the filing date, nobody yet knows the true market rent.

For the original SDLT return:

• years one to four are included at the actual contractual rent,
• year five is included using a reasonable estimate of the reviewed market rent, and
• years six and seven are included using the highest annual rent found in years one to five, based on the known figures and the estimate.

Later, the rent review is agreed. If that agreed figure for year five is higher or lower than the estimate, the tenant recalculates the NPV. If the reviewed rent changes which rent was the highest in the first five years, that may also change the figures used for years six and seven. An amended return is then sent to HMRC, and the SDLT position is adjusted accordingly.

Why this can be difficult in practice

The official example is short, but several points can be awkward in real transactions.

First, the original estimate must be reasonable. The source does not define exactly what evidence is enough, so this can be fact-sensitive. Comparable rents, valuation advice, and the wording of the review clause may all matter.

Second, the review may not be settled cleanly at the expected date. The source recognises this by referring to determination at year four, or at year five if not determined sooner. That means timing can matter. You may have a period where the review date has passed but the revised rent is still not finally fixed.

Third, the later years are not always intuitive. A reader might assume years six and seven should simply use whatever rent is actually payable in those years. The source example instead applies the specific rule based on the highest rent in any twelve-month period in the first five years. Missing that point could produce the wrong NPV.

Fourth, the source says SDLT is adjusted from thirty days after the date all uncertainty is determined. In practice, identifying when uncertainty is truly determined may itself require care, especially if there are ongoing negotiations, a review memorandum, or a formal determination process.

Key takeaways

• Where a lease rent is uncertain because of a market rent review, the initial SDLT return must still be filed using known figures and a reasonable estimate.
• For later years in this example, the calculation uses the highest rent payable in any twelve-month period in the first five years.
• Once the uncertainty is resolved, the tenant should amend the return so SDLT is recalculated, with either extra tax due or a refund for overpayment.

This page was last updated on 24 March 2026

Useful article? You may find it helpful to read the original guidance here: Stamp Duty Calculation for Leases with Variable Rent and Market Rent Revision

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