Corporate stamp duty: the 17% flat rate on £500k+ homes 2026

When a company buys a single home in England or Northern Ireland for more than £500,000, the stamp duty is not worked out the way it is for an ordinary buyer. A separate rule — the higher rate for corporate bodies in Schedule 4A of the Finance Act 2003 — charges a single flat rate of 17% on the entire purchase price.

The gap is large. On a £600,000 house, an individual home mover pays £20,000 in Stamp Duty Land Tax (SDLT). A company buying the same house as an additional property would ordinarily pay £50,000 — the standard bill plus the 5% additional-dwelling surcharge. But where the 17% flat rate applies and no relief is available, the charge is £102,000. The flat rate does not sit on top of the ordinary calculation; it replaces it, and it points sharply upward.

This explains how the rule works, who it catches, the reliefs that switch it off, and the annual charge that usually travels with it. It is general information about how the rules work, not tax or legal advice.

What Schedule 4A does

The 17% flat rate applies where all of the following are true:

• the buyer is a non-natural person — broadly a company, a partnership with a company among its members, or a collective investment scheme (a partnership made up only of individuals is not caught);
• the interest bought is a single dwelling; and
• the chargeable consideration is more than £500,000.

Because the 17% is charged on the whole price rather than in slices, the effective rate is exactly 17% at every price above the threshold. There is no nil-rate band, no taper, and the 5% additional-property surcharge is not added on top — the flat rate takes over the calculation entirely.

The 17% figure is recent. The rate was 15% from March 2012, and was raised to 17% on 31 October 2024 at the Autumn Budget — the same Budget that lifted the additional-dwelling surcharge from 3% to 5%. Transactions with an effective date on or after 31 October 2024 use the 17% rate (HMRC, 2026).

What it costs at each price

The table below compares three positions at four prices: an ordinary home mover, a company buying an additional dwelling at the standard rates plus the 5% surcharge, and the Schedule 4A flat rate. The first two columns are HMRC's own SDLT figures for England in 2026; the third column is 17% of the price.

At £1 million the difference between the ordinary bill (£43,750) and the flat-rate charge (£170,000) is nearly £126,000 — on the same house, at the same price, differing only by the identity of the buyer and whether a relief applies.

The £500,000 cliff

Because the threshold is more than £500,000, the charge behaves as a cliff rather than a slope. At exactly £500,000, a company buying an additional dwelling with no relief pays £40,000 — the £15,000 standard bill plus the £25,000 surcharge. One pound higher, at £500,001, the 17% flat rate takes over and the bill is £85,000. A single extra pound of price adds roughly £45,000 of tax (HMRC rates, 2026).

That cliff is one reason the £500,000 line matters so much in corporate purchases. It also sits alongside a separate set of rules that bite at the same figure for limited-company landlords — see the £500,000 threshold twin rules for limited-company landlords.

The reliefs that switch it off

Schedule 4A lists several reliefs that disapply the 17% rate and return the transaction to the ordinary rates — standard residential SDLT plus the 5% additional-dwelling surcharge. In broad terms they cover a dwelling bought for a genuine commercial purpose, including:

• a property rental business — a dwelling let commercially to unconnected tenants;
• property development or trading — stock bought to redevelop or resell;
• a dwelling open to the public for at least 28 days a year;
• employee or partner accommodation provided for a qualifying business;
• a farmhouse occupied with the working farmland; and
• acquisitions by financial institutions in the course of lending.

Two points matter. First, a relief has to be claimed on the SDLT return — it is not automatic. Second, there is a three-year clawback: if within three years the dwelling stops being used for the relieved purpose — for example a director or a connected individual moves in — the relief is withdrawn, the 17% charge falls due, and a further return is required (HMRC, 2026).

ATED: the annual companion charge

The same over-£500,000 envelope usually brings a second, recurring cost: the Annual Tax on Enveloped Dwellings (ATED). ATED is an annual charge on dwellings worth more than £500,000 that are held by a company or other non-natural person. It is banded by the property's value, it is based on a valuation fixed at set revaluation dates, and its bands are increased broadly in line with inflation. The categories that relieve the 17% SDLT charge — rental business, development, employee accommodation and so on — generally relieve ATED too, often reducing it to nil, but a return must still be filed to claim the relief (HMRC, 2026).

How many homes are in scope

Most homes never approach the threshold. HM Land Registry recorded 131,054 standard residential sales above £500,000 in England in 2025 — 18.7% of the 699,846 transactions in the Price Paid data (single dwellings, houses and flats, standard sales; figures fetched 9 July 2026). Only a fraction of those are bought through a corporate structure, but the numbers climb at the top: 20,698 English homes changed hands above £1 million in 2025 (3.0% of sales) — the band where the distance between a £43,750 ordinary bill and a £170,000 flat-rate charge is widest.

You can see where £500,000-plus sales concentrate by searching a prime postcode such as Westminster's SW1A 1AA on the Homecost true-cost tool, which shows the last recorded sale price and running costs for the properties on the street.

Where this sits alongside the other corporate rules

The 17% flat rate is one of several rules that treat a corporate buyer differently from an individual. It works closely with the connected-company market-value rule in section 53, which can deem a company to have paid full market value even for a gift or an under-value transfer — potentially pushing the price over the £500,000 line and into Schedule 4A territory. For more explainers on how buying costs are built up, see the other cost-intelligence guides.

For the ordinary company figure — standard rates plus the 5% surcharge — you can model any price on the stamp duty calculator. Note that the calculator produces that ordinary figure, not the Schedule 4A flat rate, which is assessed separately.

This is general information about how the rules work, not tax or legal advice. Corporate stamp duty, the Schedule 4A reliefs and ATED are technical and fact-specific, and small differences in the facts change the answer. Speak to a qualified adviser before acting.

Based on 699,846 England single-residential HM Land Registry transactions for 2025 and HMRC's published SDLT rates, fetched 9 July 2026.