Definition and Details of Right to Buy Transactions and Shared Ownership Leases

SDLT relief for right to buy sales and leases

A transaction is only treated as a right to buy transaction for SDLT if it meets a specific legal definition. This matters because, where the definition is satisfied, certain contingent payments are ignored when working out chargeable consideration, and some purchase grants linked to discounted disposals by registered social landlords are also left out.

• The rules apply to the sale of a dwelling or the grant of a lease of a dwelling, not to non-residential property.
• A qualifying transaction must either be a discounted sale or lease by a listed public sector body, or a sale or lease made under the preserved right to buy rules.
• For preserved right to buy cases, the seller must be the person against whom the right is exercisable, the buyer must be the qualifying person, and the property must be the qualifying dwelling.
• If the transaction qualifies, contingent amounts that would only be payable if a future event happens are excluded from SDLT chargeable consideration.
• Where a registered social landlord makes the discounted disposal, a related purchase grant is also excluded from chargeable consideration.
• The main practical difficulty is classification: you must check the seller’s legal status and, where relevant, the housing law conditions, rather than assuming any discounted housing purchase qualifies.

Scroll down for the full analysis.

SDLT relief for right to buy transactions: what counts as a right to buy sale

This page explains when a transaction is treated as a right to buy transaction for SDLT purposes, and why that matters. The main effect is that special SDLT rules apply to certain discounted sales or leases of dwellings by public sector and social housing bodies, including some preserved right to buy cases.

What this rule is about

SDLT is usually charged by reference to the chargeable consideration for a land transaction. In some housing transactions, that ordinary approach would produce awkward results because the buyer acquires the property at a statutory or policy discount, and the paperwork may also include future or contingent amounts.

The legislation therefore identifies a category of right to buy transactions and gives them special treatment. To decide whether that treatment applies, the first question is whether the sale or lease falls within the statutory definition of a right to buy transaction.

What the official source says

The official material says that a right to buy transaction includes either of the following:

• the sale of a dwelling at a discount, or the grant of a lease of a dwelling at a discount, by a relevant public sector body; or
• the sale of a dwelling, or grant of a lease of a dwelling, in pursuance of the preserved right to buy.

The list of relevant public sector bodies is specific. It includes central government bodies, certain local authorities, a range of social housing bodies, various new town and development bodies, certain police bodies, and some miscellaneous public bodies listed in the legislation. It also includes a body prescribed by Treasury order for this purpose.

The source also explains when a transaction is made in pursuance of the preserved right to buy. Broadly, that requires all of the following:

• the vendor must be a person against whom the preserved right to buy is exercisable under the relevant housing legislation;
• the purchaser must be the qualifying person for that preserved right to buy; and
• the dwelling must be the qualifying dwelling for that purchaser.

Where a transaction is a right to buy transaction, the normal SDLT rule on contingent consideration in Finance Act 2003 section 51(1) does not apply. The source says that chargeable consideration does not include consideration that would only become payable if a contingency occurred, or that becomes payable because a contingency has occurred.

The source also states that, where the vendor is a registered social landlord, purchase grants relating to the discounted disposal are not included in chargeable consideration.

What this means in practice

The practical point is that not every discounted purchase from a housing body is automatically a right to buy transaction for SDLT. The transaction must fall within the statutory definition.

There are three main things to check:

• Is the subject matter a dwelling?
• Is there a sale or grant of a lease at a discount by a listed public sector body, or is the transaction genuinely made under the preserved right to buy rules?
• If so, are there contingent amounts or purchase grants that would otherwise have been brought into chargeable consideration?

If the definition is met, the SDLT calculation is more limited than usual. Contingent amounts are ignored for chargeable consideration purposes in these transactions. That can matter where the documents include future payments that depend on something happening later.

It also matters where a registered social landlord is selling at a discount and a purchase grant is involved. The source says that such grants are not counted as chargeable consideration.

So the definition does more than classify the transaction. It controls how the SDLT consideration rules operate.

How to analyse it

A sensible way to analyse the issue is to work through the following questions.

1. Is there a sale or lease of a dwelling?

The source is confined to sales of dwellings and grants of leases of dwellings. If the property is not a dwelling, this particular rule does not apply.

2. Is the transaction at a discount?

For the first limb of the definition, the sale or lease must be at a discount. The source does not expand on how the discount is measured on this page, so the key point here is that the discounted nature of the transaction is part of the definition.

3. Is the seller or landlord a relevant public sector body?

This is a statutory list question. The body must fall within one of the listed categories. It is not enough that the seller performs a public or housing function in a general sense. The source sets out a defined list, including certain registered social landlords and specified public authorities.

4. If relying on preserved right to buy, are all statutory conditions met?

For preserved right to buy cases, the analysis is not just about the seller’s identity. You must also check that:

• the seller is a person against whom the preserved right is exercisable under the relevant housing legislation;
• the buyer is the qualifying person; and
• the property is the qualifying dwelling for that buyer.

If one of those elements is missing, the transaction may not be a right to buy transaction for SDLT, even if it resembles one in commercial terms.

5. Are there contingent payments in the contract?

If the transaction is a right to buy transaction, contingent consideration is excluded from chargeable consideration. This is an exception to the normal SDLT treatment. You therefore need to identify whether any part of the stated consideration only becomes payable if a future event happens.

6. Is there a purchase grant from a registered social landlord disposal?

If the vendor is a registered social landlord and there is a purchase grant in respect of the discounted disposal, the source says that grant is not included in chargeable consideration.

Example

A housing body that falls within the statutory list sells a flat to an eligible tenant at a discount under a right to buy scheme. The contract also says that an extra amount would become payable only if a specified future event occurs. If this is a right to buy transaction within the statutory definition, that contingent amount is left out when working out chargeable consideration for SDLT.

Similarly, if a registered social landlord makes the discounted disposal and a purchase grant is provided in respect of that disposal, the source says the grant is not included in chargeable consideration.

Why this can be difficult in practice

The difficult part is often classification rather than arithmetic.

First, the list of relevant public sector bodies is technical and tied to particular statutes. Some bodies have changed form over time, and some transactions involve housing stock that has moved between landlords. That means the seller’s status should be checked carefully rather than assumed.

Second, preserved right to buy cases depend on housing legislation concepts such as the qualifying person and qualifying dwelling. Those are not general SDLT concepts. A conveyancer or adviser may need to confirm that the housing-law conditions are actually met before applying the SDLT treatment.

Third, the source states the SDLT consequence for contingent consideration, but it does not on this page explain every type of future payment that might appear in transaction documents. Some drafting may look contingent but in substance may be fixed or deferred. The legal character of the payment matters.

Finally, this page is about the definition of a right to buy transaction and certain consequences for chargeable consideration. It does not set out the whole SDLT computation or all related relief provisions. So it should be read as one part of the wider SDLT framework, not as a complete code for all discounted housing acquisitions.

Key takeaways

• A right to buy transaction for SDLT is a defined category, not a loose description of any discounted housing purchase.
• If the transaction falls within that definition, contingent consideration is excluded from chargeable consideration.
• In discounted disposals by a registered social landlord, relevant purchase grants are also excluded from chargeable consideration.

This page was last updated on 24 March 2026

Useful article? You may find it helpful to read the original guidance here: Definition and Details of Right to Buy Transactions and Shared Ownership Leases

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