When a stamp duty avoidance structure tried to shrink the tax on a high-value home toward nothing, one provision was designed to put the full bill back: section 75A of the Finance Act 2003. It disregards the intermediate steps and charges Stamp Duty Land Tax (SDLT) on a single notional transaction running straight from the original seller to the eventual buyer. On a £1.5m purchase that notional charge is £93,750; on a £2m purchase it is £153,750 (HMRC 2026 rates, retrieved 3 August 2026). Those are the sums a successful section 75A challenge restores — the "prize" the backstop protects.
This is a companion to our explanation of how resting on contract and sub-sale schemes were closed, which set out the anti-avoidance rule in words. Here we put numbers on it. These are closed structures, not live options; the purpose is to show, in pounds, how completely the current rules reach through an artificial chain to the substance underneath.
What section 75A actually does
Sections 75A to 75C of the Finance Act 2003 were introduced with effect from 6 December 2006 and placed on a permanent statutory footing by the Finance Act 2007. In outline, section 75A applies where three conditions are met:
- one person (V) disposes of a chargeable interest and another (P) acquires it — or an interest deriving from it;
- a number of transactions (the scheme transactions) are involved in connection with that disposal and acquisition; and
- the SDLT actually payable on the scheme transactions is less than the tax that would be due on a single notional transaction transferring the interest directly from V to P.
Where it bites, the intermediate steps are set aside and SDLT is charged on that notional V-to-P transaction, on the largest amount of consideration passing through the chain (section 75A(4)–(5)). Sections 75B and 75C fill in which sums count and how the notional transaction is dated. HMRC sets out the mechanics in its SDLT Manual from SDLTM09050.
The rate applied to the notional transaction is the ordinary one for the interest acquired. Where the end result is the acquisition of a dwelling, that is the standard residential SDLT table — the same slabs any buyer of the same house at the same price would face.
The prize, priced
A scheme built on resting on contract or an abusive sub-sale aimed to leave close to £0 payable, on the argument that no single leg of the chain was a completed, chargeable purchase. Section 75A answers that the tax is due on the whole V-to-P move regardless. The gap between the two — near-nil versus the full standard bill — is exactly what the provision recovers.
| Purchase (V → P) | SDLT on the notional transaction | What the closed scheme aimed to leave payable | Amount section 75A restores |
|---|---|---|---|
| £1,000,000 | £43,750 | ≈ £0 | £43,750 |
| £1,500,000 | £93,750 | ≈ £0 | £93,750 |
| £2,000,000 | £153,750 | ≈ £0 | £153,750 |
Effective rates on those notional charges run 4.38% at £1m, 6.25% at £1.5m and 7.69% at £2m — the standard residential figures returned by the Homecost stamp duty calculator on 3 August 2026 for a UK-resident buyer of a single main residence (no first-time-buyer relief, no additional-property surcharge). A surcharged buyer would face more again; at £1.5m the additional-property bill is £168,750.
Where the charge is built up
The six-figure totals are not a single flat rate. Standard residential SDLT is a slab system, and most of the notional charge at the top of the market comes from the highest two bands. Taking the £1.5m case:
| Slice of the £1.5m price | Rate | Tax on the slice |
|---|---|---|
| £0 – £125,000 | 0% | £0 |
| £125,000 – £250,000 | 2% | £2,500 |
| £250,000 – £925,000 | 5% | £33,750 |
| £925,000 – £1,500,000 | 10% | £57,500 |
| Total | — | £93,750 |
The 10% band alone accounts for £57,500 of the bill; a purchase that only just clears £925,000 carries £36,250. Because the notional charge tracks the ordinary table exactly, it climbs with price in the same way an honest purchase would:
| Purchase price | Standard residential SDLT (2026) |
|---|---|
| £925,000 | £36,250 |
| £1,000,000 | £43,750 |
| £1,250,000 | £68,750 |
| £1,500,000 | £93,750 |
| £2,000,000 | £153,750 |
This is also why timing matters in ordinary transactions, not only avoidance ones: the moment a purchase is treated as effected fixes which rate table applies. Our guide to substantial performance versus completion sets out how that effective date is decided.
How thin this slice of the market is
The prices at which section 75A charges reach six figures sit at the very top of the market. Of 763,112 standard price-paid transactions recorded in England and Wales for 2025 (HM Land Registry), 23,014 — 3.02% — reached £1m, 8,292 (1.09%) were at or above £1.5m, and 3,779 (0.5%) at or above £2m. Figures retrieved 3 August 2026.
That thin top end is where the notional-charge arithmetic actually lives. Fewer than one standard sale in ninety crosses the £1.5m line where the £93,750 figure begins, which is precisely why the schemes that once targeted it were worth constructing — and why the backstop that answers them is written in six figures rather than four.
No motive required
A common misunderstanding is that section 75A only applies to deliberate avoidance. The Supreme Court held otherwise in Project Blue Ltd v HMRC [2018] UKSC 30, the Chelsea Barracks case, which involved a sub-sale combined with a finance leaseback. The court confirmed that section 75A is mechanical: it requires no tax-avoidance motive. If the actual SDLT on the scheme transactions comes out below the notional charge and the statutory conditions are met, the provision bites whatever the parties intended.
The practical reach of that ruling is why the numbers above matter beyond history. Getting an SDLT position wrong — through an aggressive structure or an honest error over a chain of transfers — exposes the shortfall plus interest and penalties, a stack set out in our guide to the full stamp duty consequence stack.
The through-line
Section 75A does not create a new tax. It restores the ordinary charge — the same bill a straightforward buyer of the same dwelling at the same price would pay — when a chain of steps has tried to make that charge disappear. Priced out, that is £43,750 at £1m, £93,750 at £1.5m and £153,750 at £2m: the exact sums the notional transaction puts back.
You can see how those headline bands feed into a real all-in monthly cost for any street — including the top-end postcodes where these structures once lived, such as Westminster (SW1A 1AA) — with the Homecost postcode tool. For more on how the tax works across price points, browse the cost intelligence guides.
This article explains how the rules operate; it is general information, not tax or legal advice, and every transaction turns on its own facts. Speak to a qualified adviser before acting.
Figures based on 763,112 HM Land Registry standard price-paid transactions for England and Wales in 2025 and HMRC 2026 SDLT rates. More cost guides.