Sub-Sale Relief: Section 45 FA2003 Explained

What Is Sub-Sale Relief?

Sub-sale relief is a specific SDLT relief contained in section 45 of the Finance Act 2003. It applies where the original purchaser of a property (B) does not take the conveyance of the land itself but instead assigns the benefit of the contract — or a sub-sale is effected — to a third party (C) before completion takes place.

In the absence of this relief, both B and C would potentially face SDLT charges: B on the original A–B transaction, and C on the assignment. The relief prevents this double taxation by exempting B entirely. Only C pays SDLT — and C pays on the consideration C provides (or the original A–B price, whichever is higher under the chargeable consideration rules).

The policy rationale is to facilitate property trading and development finance without imposing a double SDLT charge where the intermediate party never receives the legal title and acts essentially as a conduit.

Conditions for Relief Under s45

Section 45 FA2003 as amended sets out the conditions that must be satisfied for B to claim sub-sale relief:

If all four conditions are met, B is treated as if the original contract was rescinded — B has no SDLT liability. The only notifiable transaction is the sub-sale from B to C, and C files the SDLT return and pays the tax.

Worked Example: A–B–C Chain

A developer (A) contracts to sell a residential property to an investor (B) for £400,000. Before completion, B assigns the contract to a new purchaser (C) for £450,000. A conveys the property directly to C.

B's profit on the assignment (£50,000) is subject to income tax or corporation tax as a trading profit — it is not SDLT. The relief only affects stamp duty, not direct tax on B's gain.

Exclusions: Post-Completion & Separated Contracts

Post-Completion Assignment

This is the most commonly misunderstood limitation. Once A completes the conveyance to B, sub-sale relief is permanently unavailable. If B then sells to C, that is an entirely separate transaction — a standard residential sale where B pays SDLT on A–B and C pays SDLT on B–C. There is no mechanism to retrospectively claim sub-sale relief after B has accepted legal title.

Separated Contracts

Section 45 applies where there is a single original contract that is assigned. Where the arrangement involves two wholly separate contracts — A contracts with B, and separately B contracts with C, each on their own terms — HMRC may take the view that this is not a true sub-sale but two separate transactions, and the relief cannot be claimed.

Connected Party Denial

Sub-sale relief is expressly denied where B and C are connected persons within the meaning of section 1122 CTA2010 (formerly s839 ICTA1988). Connected persons include:

• Spouses and civil partners
• Relatives (siblings, ancestors, lineal descendants) and their spouses
• Business partners and their relatives
• A company controlled by B or any of the above persons
• A company under common control with B

The connected party denial exists to prevent what would otherwise be a straightforward avoidance structure: B (connected to C) buys from A, assigns to C before completion, both claim they have separate interests, yet effectively B has acquired the property with C as the nominal purchaser.

Timing Is Critical

The entire relief hinges on the assignment occurring before completion of the original A–B contract. "Completion" for SDLT purposes is the date on which the conveyance is executed — typically the day the legal title passes. If there is any ambiguity about whether the assignment was before or after this moment, HMRC will scrutinise the sequence of events closely.

In practice, the assignment and the sub-sale should be documented on paper with clear dates, and the assignment should be effected by a formal deed of assignment that precedes the completion date. Relying on oral agreements or informal arrangements as to timing will not suffice.

Practical Applications

Frequently Asked Questions