Guide to Key Terms in Additional Dwelling Supplement Legislation

Key terms for Scotland’s Additional Dwelling Supplement (ADS)

Scotland’s ADS is an extra amount of LBTT on some purchases of residential property. Whether it applies depends on the effective date of the transaction, what dwellings the buyer is treated as owning at that date, whether the property counts as a dwelling, whether the buyer is replacing their main home, and how much of the price is chargeable for ADS.

• The effective date is usually settlement or completion, but it can be earlier, for example on substantial performance of the contract.
• Ownership is defined widely and can include joint ownership, long residential leases, trust or liferent interests, rights to become owner, and homes anywhere in the UK or overseas.
• From 1 April 2024, a share worth under £40,000 is usually ignored, but family attribution rules can still combine interests of spouses, civil partners, cohabitants, and certain children under 16.
• A dwelling includes a building used or suitable for use as a single home, including holiday homes and land enjoyed with it, but usually not a cleared site with only planning permission.
• If the buyer will own two or more dwellings, ADS may still be avoided if they are replacing their only or main residence; the look-back period is 18 months up to 31 March 2024 and 36 months from 1 April 2024.
• ADS is charged at 8% of the relevant residential consideration, with a just and reasonable apportionment needed for mixed-use or multiple-property transactions.

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ADS key terms for LBTT: effective date, ownership, dwellings, replacing a main residence, and chargeable consideration

This page explains the main concepts used when deciding whether Scotland’s Additional Dwelling Supplement (ADS) applies to a land transaction. These terms matter because ADS is charged by reference to what the buyer owns, what is being bought, whether the buyer is replacing a main residence, and how much of the price counts for ADS purposes.

What this rule is about

ADS is an extra amount of LBTT charged on certain purchases of dwellings. To work out whether it applies, you need to answer a series of linked questions:

• What is the transaction’s effective date?
• Who is treated as owning dwellings at that date?
• What counts as a dwelling?
• Is the buyer replacing their only or main residence?
• What amount is ADS charged on?

Revenue Scotland’s guidance brings these points together because they are the building blocks of the ADS rules. A small change in facts can alter the result, especially where there are joint buyers, family ownership, trust interests, leasehold interests, mixed property, or recent separation.

What the official source says

The official guidance says the following.

The effective date for ADS purposes is the date LBTT liability arises. In an ordinary purchase, that is usually settlement or completion. In some cases it is earlier, such as substantial performance of a contract before completion. The guidance also notes that if a contract is conditional, the contract date will usually still be taken as the date the conditional contract was entered into, because the contract is binding at that point.

Ownership is wider than simple registered title. A person can be treated as an owner if they have registered title, if they are entitled to become the owner, if they hold certain trust or liferent interests, or if they are a tenant under a long residential lease of more than 20 years. Dwellings outside Scotland also count if the person would be treated as owning them were they in Scotland. For ADS purposes, a buyer is treated as owning the purchased property at the end of the effective date, even though Scots property law normally requires registration before ownership is completed.

Where ownership is joint, each joint owner is treated as owning the dwelling. The economic unit rules can also attribute ownership between spouses, civil partners, cohabitants, and certain children under 16. Those rules do not apply where the parties have separated, no longer live together, and do not intend to resume living together.

For transactions with an effective date on or after 1 April 2024, a share worth less than £40,000 is not treated as ownership for these purposes. But the guidance says the economic unit rules can still aggregate interests across the family unit so that if the total shares held reach £40,000 or more, the dwelling is treated as owned by each individual in that unit for ADS purposes.

Also for transactions with an effective date on or after 1 April 2024, there is an exception where a person retains an interest in a former main residence because of a court order or formal agreement connected with divorce, separation, dissolution, or annulment, and that property remains the main residence of their spouse, civil partner, former spouse, or former civil partner. In those circumstances, buying a second dwelling can be exempt from ADS if the stated conditions are met.

A dwelling means a building or part of a building that is used or suitable for use as a single dwelling, or is being constructed or adapted for that use. Land enjoyed with the dwelling, such as garden or grounds, is part of it. A building still counts as a dwelling even if it is to be refurbished or demolished. Holiday homes and holiday lets can count as dwellings, even if they cannot be used all year round. By contrast, a cleared site with no building is not a dwelling merely because it has planning permission. Caravans, mobile homes and houseboats are usually not dwellings unless they have become sufficiently fixed to the land.

Dwellings anywhere in the UK or overseas are counted, not just Scottish dwellings. The market value test also matters. Only dwellings with a market value of at least £40,000 are counted. For transactions on or after 1 April 2024, a share worth less than £40,000 does not count. The valuation must be a reasonable estimate as at the effective date, and evidence should exist if the property is not being sold. The guidance also says there must be no artificial separation of interests or rights when valuing ownership.

Where the person’s ownership is through a long lease, the relevant value is the value of that ownership interest, not the value of the dwelling itself. But where the person is a beneficiary with a relevant trust interest or a liferenter, the relevant value is the value of the dwelling itself, including related ownership rights, and ignoring any reduction caused by the existence of the beneficiary’s or liferenter’s own interest.

The question whether an only or main residence is being replaced applies only to purchases by individuals. It does not apply to individuals buying in the course of a property investment or property dealing business, and it does not apply to non-natural persons.

If, at the end of the effective date, the buyer owns only one dwelling, ADS does not apply and there is no need to ask whether a main residence is being replaced. If the buyer owns two or more dwellings, the replacement question becomes important. If a main residence is being replaced, ADS does not apply. If the old main residence has not yet been sold, ADS applies, although a repayment may be available if that former main residence is sold within the relevant time limit.

The guidance states that the time limit is 18 months for transactions with effective dates up to 31 March 2024, and 36 months for transactions with effective dates on or after 1 April 2024.

To identify a person’s main residence, Revenue Scotland applies a factual test. A person can have only one main residence at a time for ADS purposes. There is no election. It is usually the place where the person lives and spends most of their time, judged by factors such as where possessions are kept, where family lives, where the person is registered with organisations, where children attend school, and where the person is registered to vote. Temporary absences do not necessarily change the answer. But temporary or stop-gap occupation may not be enough to establish a main residence. If a property is rented out so that the person is not entitled to live there, it cannot be their main residence during that period.

The replacement test is a two-stage test. The buyer must have disposed of a dwelling that was their only or main residence within the relevant 18-month or 36-month period before the effective date of the new purchase, and must intend to occupy the new dwelling as their only or main residence on that effective date. Leaving rented accommodation is not a disposal because the person did not own it.

As for the amount charged, ADS is charged at 8% of the relevant consideration. In a standard residential purchase, that will usually be the chargeable consideration, normally the purchase price. In a transaction involving both residential and non-residential property, ADS applies only to the just and reasonable residential portion. If that residential portion is less than £40,000, ADS does not apply. If the transaction includes more than one property and one of them is intended to be the buyer’s only or main residence, the guidance says the amount subject to ADS excludes, on a just and reasonable basis, the amount attributable to that intended main residence.

What this means in practice

The ADS analysis is not just about the property being bought. It is equally about the buyer’s wider position at the end of the effective date.

In many ordinary house moves, ADS will not apply because the buyer sells their old main residence and buys the new one at the same time. But the result changes if the buyer keeps the old property, owns another dwelling anywhere in the world, buys jointly with someone who already owns another dwelling, or is caught by the economic unit rules.

The ownership rules are particularly important because they go beyond straightforward legal title. Someone may think they do not own another dwelling because they are not on the title sheet, but they may still be treated as an owner through an uncompleted entitlement, a trust interest, a liferent, or a long lease. Equally, joint ownership means each joint owner is treated as owning the whole dwelling for counting purposes.

The 1 April 2024 changes are significant in two ways. First, small shares worth less than £40,000 are generally ignored. Secondly, the look-back period for replacing a main residence increased from 18 months to 36 months for transactions with effective dates on or after that date.

The main residence rules are practical rather than formal. You cannot simply choose which home is your main residence. Revenue Scotland looks at the reality of occupation and intention. A property that was once your home may stop being your main residence if you move out with no real expectation of returning, especially if it is rented to someone else.

Mixed purchases also need care. If a transaction includes both residential and non-residential property, ADS is not necessarily charged on the full price. The residential element must be identified on a just and reasonable basis. The same approach applies where more than one property is acquired and one is intended to be the buyer’s main residence.

How to analyse it

A sensible way to approach ADS is to work through the questions in order.

• Identify the effective date. Do not assume this is always completion. Check whether substantial performance occurred earlier.
• List every dwelling the buyer is treated as owning at the end of that date. Include Scottish, UK and overseas property.
• Check deemed ownership rules. Is there a trust interest, liferent, long lease, unregistered entitlement, or joint ownership?
• Apply the economic unit rules. Consider spouses, civil partners, cohabitants, and relevant children under 16, unless the separation exception applies.
• Check value. Is each dwelling, or relevant share, worth at least £40,000 on the effective date?
• Ask whether the property in question is a dwelling at all. A habitable or suitable building usually is. A cleared site usually is not.
• If the buyer will own only one dwelling at the end of the day, ADS should not apply.
• If the buyer will own two or more dwellings, ask whether they are replacing an only or main residence.
• For replacement, apply the two-stage test: was a former main residence disposed of within the relevant period, and does the buyer intend to occupy the new dwelling as their only or main residence on the effective date?
• If the transaction is mixed or includes multiple properties, identify the amount of chargeable consideration properly attributable to the residential element or to the relevant dwellings on a just and reasonable basis.

Documents and evidence may matter. Examples include title records, trust documents, lease terms, separation agreements, court orders, valuation evidence, and evidence showing where the buyer actually lived and intended to live.

Example

Illustration: A buyer owns a holiday cottage and lives in a flat that they own. On 10 May 2025 they buy a house which they intend to move into as their new main residence. They keep the holiday cottage. If they sell the flat that was their main residence within the 36 months before 10 May 2025, and the new house is intended to be their main residence on that date, the Revenue Scotland guidance indicates that ADS will not apply, even though they still own the holiday cottage.

By contrast, if they keep the flat and simply buy the new house, they will own at least two dwellings at the end of the effective date and will not have disposed of the former main residence. On those facts, ADS would apply unless some other exception covers the case.

Why this can be difficult in practice

Several parts of the ADS rules are fact-sensitive.

Main residence is often the hardest issue. The guidance gives indicators, but no single factor is decisive. People may divide time between homes, live away for work, stay temporarily with family, or move into rented accommodation between purchases. In those situations, the answer depends on the overall facts and the buyer’s settled pattern of life.

Valuation can also be difficult, especially where only a share is held, the property is overseas, or the interest is unusual. From 1 April 2024, the £40,000 threshold for shares can be crucial, but the economic unit rules may still bring the dwelling back into account when family holdings are aggregated.

Another area needing care is the interaction between Scots property law and the ADS deeming rules. In ordinary Scots law, ownership usually completes on registration. But for ADS, the buyer is treated as owning the purchased dwelling at the end of the effective date. That means the count of dwellings can change immediately for tax purposes even before registration is complete.

Mixed transactions and multiple-property transactions can also create room for disagreement because the guidance relies on a just and reasonable apportionment. That is a familiar tax concept, but it is not a mechanical formula. The chosen split should be supportable by the facts.

Key takeaways

• ADS depends on the buyer’s position at the end of the effective date, not just on the property being bought.
• Ownership is defined broadly and can include joint interests, trust interests, liferents, long leases, and family attribution under the economic unit rules.
• Where the buyer owns two or more dwellings, the main question is often whether they are genuinely replacing an only or main residence within the relevant time limit.

This page was last updated on 24 March 2026

Useful article? You may find it helpful to read the original guidance here: Guide to Key Terms in Additional Dwelling Supplement Legislation

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