The additional-property surcharge adds 5% to every SDLT band above £40,000 when you buy a residential property and you'll own another residential property at the end of completion. It applies to buy-to-let investors, second-home buyers, holiday-home owners, parents helping children buy, and anyone who'll own more than one residential property in the UK or abroad at the end of completion day. This guide covers the full rules, the joint-ownership and inheritance edge cases, reclaim mechanics, and the planning options worth considering.

The headline rule

If, at the end of the day on which you complete a residential property purchase, you own more than one residential property anywhere in the world, you pay the 5% additional-property surcharge on every band above the £40,000 threshold. The new purchase isn't "replacing" your main residence.

The rule is binary: ownership of any other property at end-of-completion-day triggers the surcharge. It doesn't matter how the other property is used (rental, holiday, empty, abroad), how much it's worth, or what share you hold (with limited inheritance exceptions covered below).

The 2026 rate table

Portion of property price	Standard rate	+ Surcharge	Additional rate
Up to £125,000	0%	+5%	5%
£125,001 – £250,000	2%	+5%	7%
£250,001 – £925,000	5%	+5%	10%
£925,001 – £1,500,000	10%	+5%	15%
Over £1,500,000	12%	+5%	17%

Use the BTL SDLT calculator or second home SDLT calculator for the precise figure at your price. Non-UK residents add an additional 2% on top.

Joint ownership scenarios — the most common edge cases

Married couples

For SDLT purposes, married couples and civil partners are treated as a single economic unit. If either spouse owns another residential property anywhere in the world, the new purchase by either of them is treated as additional property — even if the other spouse doesn't own anything.

The only exception is where the couple is formally separated under a court order. Informal separation is not enough to escape the deemed-ownership rule.

Unmarried couples

Unmarried co-buyers are treated as separate individuals. The surcharge applies if any one of them already owns another residential property. But the ownership doesn't extend to "deemed" ownership of a non-buying partner's property. So an unmarried couple where only one owns the existing home can buy a new property in the non-owning partner's sole name without triggering the surcharge.

This is a meaningful planning point. For unmarried co-buyers, careful ownership structuring can avoid the surcharge entirely on the second property; for married couples no equivalent structure works.

Parents helping children

A parent who already owns their home wants to help their adult child buy a flat. The structure matters:

• Parent on the deeds: Surcharge applies to the whole purchase, because the parent owns another property.
• Parent provides funds, child sole legal owner: No surcharge applies (assuming child owns nothing else). This is the cheaper structure.
• Parent as guarantor on the mortgage: No SDLT impact — guarantor status doesn't trigger the surcharge.
• Joint Borrower Sole Proprietor (JBSP) mortgage: Parent on mortgage but child sole legal owner. No surcharge because parent isn't on the deeds.

The £40,000 cliff edge

The surcharge only applies if the purchase price is £40,000 or more. Below that, standard SDLT rates apply (which in practice means £0 for sub-£40k residential property because the standard nil-rate band runs to £125k).

The £40,000 threshold is a sharp cliff:

• Purchase at £39,999: Standard SDLT only, £0 total.
• Purchase at £40,001: Full surcharge on the entire price = £2,000.50
• The £2 price difference triggers ~£2,000 of tax.

In 2026, sub-£40k residential property is rare in the UK. The threshold mainly affects regional landlords buying entry-level stock, garage conversions with separate title, and certain auction lots.

Inherited property — the 3-year window

Inheriting a residential property doesn't permanently lock you into "multiple owner" status for surcharge purposes. If you inherited 50% or less of the property AND you buy a different property within 3 years of the inheritance, the inherited property doesn't count toward the surcharge test on the new purchase.

Worked scenarios:

• You inherit a 33% share with two siblings. Below 50% — relief applies if you buy within 3 years.
• You inherit 50% with one sibling. Exactly 50% — relief applies (50% or less qualifies).
• You inherit 100% as sole beneficiary. Above 50% — full surcharge applies on the new purchase.
• 3-year clock starts the day you become the legal owner (typically the date of grant of probate, not the date of death).

Replacement of main residence — the 36-month rule

The biggest legitimate way to avoid the surcharge is the "replacement of main residence" rules. If your new purchase is your replacement main residence (and the old one is being or has been sold), the surcharge either doesn't apply or is reclaimable.

Three scenarios:

• Sale completes before new purchase: No surcharge on the new purchase. The simplest scenario.
• Same-day sale and purchase completion: No surcharge. Most home-mover transactions structure this way.
• New purchase completes before sale of old property: Surcharge applies initially. If the old property sells within 36 months, you can reclaim the 5% surcharge portion via Form SDLT16.

The reclaim time limit is 12 months from the date of sale of the old property (or 12 months from the SDLT filing deadline of the new purchase, whichever is later). Use the SDLT refund calculator to model the reclaim figure.

Worked examples at common prices

Property price	Standard SDLT	Additional property SDLT	Surcharge cost
£150,000	£500	£7,500	+£7,000
£200,000	£1,500	£11,500	+£10,000
£250,000	£2,500	£15,000	+£12,500
£350,000	£7,500	£25,000	+£17,500
£450,000	£12,500	£35,000	+£22,500
£600,000	£20,000	£50,000	+£30,000
£800,000	£30,000	£70,000	+£40,000
£1,000,000	£41,250	£91,250	+£50,000

Multiple Dwellings Relief — no longer available

Multiple Dwellings Relief (MDR) was abolished for purchases completing on or after 1 June 2024. Before abolition, MDR allowed buyers of 2+ dwellings in a single transaction to calculate SDLT on the average price per dwelling, often producing meaningful savings. That route is no longer available except for transitional cases (contracts exchanged before 1 June 2024).

The only remaining "multiple dwellings" SDLT relief is the 6+ dwellings rule: buying 6 or more dwellings in a single transaction can be treated as non-residential property, attracting the lower non-residential rates without the additional-property surcharge. This is the main remaining planning lever for large portfolio acquisitions.

Scotland and Wales — different surcharge structures

The 5% English/NI surcharge applies only in England and Northern Ireland. Devolved jurisdictions use materially different structures:

Scotland — LBTT with 8% ADS

The Land and Buildings Transaction Tax (LBTT) Additional Dwelling Supplement is a flat 8% of the whole purchase price (since 5 December 2024 — increased from 6%), applied on top of standard LBTT. So on a £300,000 additional-property purchase in Scotland:

• Standard LBTT: £4,600
• ADS: 8% × £300,000 = £24,000
• Total: £28,600

Use the LBTT calculator for the precise figure.

Wales — LTT with banded higher rates

The Welsh Land Transaction Tax higher residential rates use a separate banded structure (since 11 December 2024):

• 5% up to £180,000
• 8.5% £180,001 – £250,000
• 10% £250,001 – £400,000
• 12.5% £400,001 – £750,000
• 15% £750,001 – £1,500,000
• 17% over £1,500,000

Use the LTT calculator for the precise figure.

Non-UK residents — additional 2% surcharge

Non-UK residents (defined as not present in the UK for at least 183 days in the 12 months ending on completion) pay an additional 2% on top of standard SDLT. Combined with the 5% additional-property surcharge (if applicable), a non-UK-resident BTL buyer pays:

• 7% on the first £125k (0% standard + 5% surcharge + 2% non-resident)
• 9% on £125-250k
• 12% on £250-925k
• 17% on £925k-1.5m
• 19% on over £1.5m

Use the non-UK resident calculator for the precise figure including all surcharges.

Common misconceptions about the surcharge

The additional-property surcharge attracts more confusion than any other SDLT rule. Four myths worth correcting:

• "The surcharge only applies if I'm renting it out." Wrong — what you'll do with the property is irrelevant. The trigger is ownership at end of completion day, not intended use.
• "If I buy in cash, the surcharge doesn't apply." Wrong — cash buyers pay SDLT on the same banded structure. There's no cash-purchase exemption.
• "My overseas holiday home doesn't count." Wrong — the surcharge looks at worldwide residential property ownership.
• "My company can be a first-time buyer." Wrong — companies are non-natural persons. They never qualify for first-time buyer relief, and they always pay additional-property rates on residential purchases.

Frequently asked questions

What is the additional property stamp duty surcharge?

The additional-property surcharge is an extra 5% of SDLT applied to every band above £40,000 when buying a residential property if you'll own more than one residential property at the end of completion day.

Who pays the 5% surcharge?

Anyone who will own more than one residential property at the end of completion day — including buy-to-let investors, second-home buyers, parents going on the deeds with children, and companies. Joint purchases trigger the surcharge if ANY buyer already owns another property.

When does the £40,000 threshold matter?

The surcharge only applies if the purchase price is £40,000 or more. Below that, standard SDLT rates only (which means £0 for sub-£40k residential). The threshold creates a cliff: £39,999 = no SDLT, £40,001 = full surcharge.

Can I reclaim the surcharge?

Yes, if you paid the surcharge because you temporarily owned two properties (your previous main home hadn't sold). Sell the previous main home within 36 months and reclaim via HMRC Form SDLT16. Pure BTL/second-home purchases cannot reclaim.

Are there any exemptions?

Yes — purchases below £40,000; replacement of main residence; purchases of 6+ dwellings (non-residential rate); some inherited property with 50% or less share and purchase within 3 years; certain leases under 21 years; and other technical exemptions.

What about inherited property?

Inheriting a residential property doesn't trigger the surcharge if you inherited 50% or less AND you buy within 3 years of becoming the legal owner. Above 50% share, full surcharge applies.

Do joint owners both pay the surcharge?

No — the surcharge is on the total purchase, not per buyer. But if any joint buyer already owns another property, the surcharge applies to the whole purchase. Shares of ownership don't reduce the surcharge.

What about Scotland and Wales?

England/NI uses the 5% banded surcharge. Scotland uses LBTT's 8% Additional Dwelling Supplement (flat). Wales uses LTT's higher residential rates (a separate banded structure).

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Last reviewed: 25 May 2026.