What is the additional dwelling supplement for stamp duty?
Answered 11 March 2026
SDLT Higher Rates for Additional Dwellings
Note: In England and Northern Ireland, this is known as the Higher Rates for Additional Dwellings (HRAD) under SDLT — not "Additional Dwelling Supplement" (which is the Scottish equivalent). The answer below covers the English/Northern Irish SDLT position.
What the Law Says
The higher rates for additional dwellings are provided for in Schedule 4ZA to the Finance Act 2003, inserted by section 128(3) of the Finance Act 2016. Schedule 4ZA modifies section 55 FA 2003 (the general charging provision) for transactions that qualify as "higher rates transactions".
The rates as originally enacted (Schedule 4ZA, Table A) were set at a flat surcharge above the standard residential bands:
| Relevant Consideration | Higher Rate |
|---|---|
| Up to £125,000 | 3% |
| £125,001 – £250,000 | 5% |
| £250,001 – £925,000 | 8% |
| £925,001 – £1,500,000 | 13% |
| Remainder | 15% |
From 31 October 2024, the higher rates were increased and are now 5 percentage points above the standard residential rates (having previously been 3 percentage points above).
A transitional rule applies: where a contract was entered into on or before 30 October 2024 but completes or is substantially performed after that date, the higher rates apply at the pre-31 October 2024 rate of 3 percentage points above the standard residential rates — unless the contract is subsequently varied, assigned, or otherwise altered.
HMRC Guidance / Practice
Scope — what transactions are caught:
The higher rates apply from 1 April 2016 to purchases of:
- Additional dwellings — such as second homes and buy-to-let properties, including the purchase of a new main residence where the old main residence is still owned; and
- All dwellings purchased by companies.
Additional surcharges that can stack on top:
- A further 2% non-resident surcharge applies on top of all other residential SDLT rates (including the higher rates for additional dwellings) for non-UK resident purchasers on transactions with an effective date on or after 1 April 2021.
Rate history summary (per HMRC guidance):
- From 1 April 2016: 3 percentage points above standard rates
- From 31 October 2024: increased to 5 percentage points above standard rates
⚠️ Important: The standard residential SDLT rates (to which the 5-point surcharge is added) were themselves subject to temporary changes (e.g. the nil-rate threshold was temporarily raised to £250,000 between 23 September 2022 and 31 March 2025, reverting to £125,000 from 1 April 2025). The surcharge is always calculated as a fixed number of percentage points above whichever standard rates are in force at the effective date of the transaction.
Citation sources
Autumn Statement 2015 announced that Higher Rates of Stamp Duty Land Tax (SDLT) would apply from 1 April 2016 to purchases of: additional dwellings – such as second homes and buy-to-let properties, including the purchase of a new main residence where old main residence is still owned. all dwellings by companies. The legislation passed into law as Schedule 4ZA of Finance Act 2003, as inserted by section 128(3) of the Finance Act 2016. Schedule 4ZA was subsequently amended by the Finance Act 2018
The higher rates were increased for transactions with an effective date on or after 31 October 2024. Following the increase, the higher rates are 5 percentage points above the standard residential rates of SDLT. Contracts entered into before 31 October 2024 Where a contract was entered into on or before 30 October 2024 but completes or is substantially performed after that date, the higher rates will apply to that transaction at the pre-31 October 2024 rate of 3 percentage points above the stan
At Budget 2020, the Government announced a 2% Stamp Duty Land Tax ("SDLT") surcharge on purchases of dwellings in England and Northern Ireland made by non-UK resident purchasers, including certain UK resident companies controlled by non-residents. The surcharge applies to purchases with an effective date on or after 1 April 2021. The surcharge applies on top of all other residential rates of SDLT, including the rates which apply to first time buyers, purchases of additional dwellings, purchases
PART 8 SDLT and ATED Stamp duty land tax SDLT: higher rates for additional dwellings etc 128 1 FA 2003 is amended in accordance with subsections (2) to (4). 2 In section 55 (amount of tax chargeable: general) after subsection (4) insert— 4A Schedule 4ZA (higher rates for additional dwellings and dwellings purchased by companies) modifies this section as it applies for the purpose of determining the amount of tax chargeable in respect of certain transactions involving major interests in dwellings
The freehold of a new block of 20 flats is purchased for £2.5 million. There is no headlease and none of the flats is subject to a long lease. The transaction is a relevant transaction for the purposes of the relief as it involves the acquisition of more than one dwelling - i.e. the 20 flats. The freehold is treated as if it were interests in the individual dwellings. The chargeable consideration divided by the number of dwellings is £125,000. This is below the normal 0% SDLT threshold but a min