Additional Property SDLT Surcharge (2026): Complete Guide

If you're buying a second home, a buy-to-let property, or a holiday cottage in England or Northern Ireland, you'll pay an extra 5% Stamp Duty Land Tax (SDLT) on top of the standard rates. This "additional property surcharge" was increased from 3% to 5% in October 2024, making second property purchases significantly more expensive. The surcharge applies to the entire purchase price—not just the portion above certain thresholds—and catches many buyers by surprise. This guide explains exactly when you'll pay it, how much it costs, and the circumstances where you might avoid it or claim a refund.

What is the additional property SDLT surcharge?

The additional property surcharge is an extra layer of Stamp Duty Land Tax you pay when buying a residential property if you already own another residential property anywhere in the world worth £40,000 or more. It was introduced in April 2016 to cool the buy-to-let market and help first-time buyers compete, and the rate jumped from 3% to 5% for completions on or after 31 October 2024.

The surcharge applies to:

Buy-to-let properties you're purchasing to rent out
Second homes including holiday homes and weekend retreats
Properties bought through a company (though companies face different rules—see below)
Any additional residential property even if you're buying it for a family member to live in

The key test is simple: at the end of the day you complete your purchase (when the property legally becomes yours), do you own any other residential property worth £40,000 or more? If yes, you pay the surcharge.

How much is the surcharge?

The surcharge adds 5 percentage points to every SDLT band. Here's what you actually pay for an additional property in 2026-27:

| Property price portion | Standard SDLT rate | Additional property rate | |------------------------|-------------------|-------------------------| | Up to £250,000 | 0% | 5% | | £250,001 to £925,000 | 5% | 10% | | £925,001 to £1.5 million | 10% | 15% | | Above £1.5 million | 12% | 17% |

Notice that you pay 5% even on the first £250,000—the portion that would normally be tax-free disappears entirely when the surcharge applies.

Example: Buying a £300,000 buy-to-let property

Let's say you already own your main home and you're buying a £300,000 flat to rent out:

First £250,000: £250,000 × 5% = £12,500
Next £50,000: £50,000 × 10% = £5,000
Total SDLT: £17,500

If this were your only home (no surcharge), you'd pay just £2,500. The surcharge has added £15,000 to your bill.

Example: Buying a £600,000 holiday home

You own a house in Manchester and you're buying a cottage in the Lake District for £600,000:

First £250,000: £250,000 × 5% = £12,500
Next £675,000: £350,000 × 10% = £35,000
Total SDLT: £47,500

Without the surcharge, you'd pay £20,000. The surcharge adds £27,500.

When does the surcharge apply?

The surcharge applies if all three of these conditions are met:

You're buying a residential property (not commercial premises, not bare land)
The purchase price is £40,000 or more
At completion, you own at least one other residential property worth £40,000 or more anywhere in the world

What counts as "owning" another property?

You're treated as owning a property if:

You own it outright
You own it jointly with someone else (even if you only own 1%)
You own it through a trust where you're a beneficiary
Your spouse or civil partner owns it (married couples and civil partners are treated as a single unit for SDLT purposes)

It doesn't matter whether:

The other property has a mortgage on it
You live in the other property or rent it out
The other property is in the UK or abroad
You inherited the property or bought it

What counts as a "residential property"?

A property is residential if someone could live in it as a home. This includes:

Houses and flats
Cottages and bungalows
Houseboats and mobile homes (if suitable for year-round living)
Properties you're renovating to live in or rent out

It doesn't include:

Commercial property (shops, offices, warehouses)
Agricultural land without a dwelling
Property that's uninhabitable and being demolished

When the surcharge doesn't apply

There are several important exceptions where you won't pay the surcharge even if you own another property:

1. Replacing your main home

If you're selling your current main home and buying another one to live in, you don't pay the surcharge—provided you sell your old main home within 36 months of buying the new one.

This works in two ways:

Option A: Sell first, buy second If you sell your old home before or on the same day you buy the new one, you simply don't pay the surcharge.

Option B: Buy first, sell second If you buy your new main home before selling the old one (perhaps because you need somewhere to move into), you'll initially pay the surcharge. But you can claim a full refund if you sell your old home within 36 months and the new property becomes your main residence.

To claim the refund, you must submit an amended SDLT return (form SDLT1) within 12 months of selling your old home, or within 12 months of the filing date for the original return, whichever is later [Finance Act 2003 Sch 4ZA].

Example: Moving home with overlap

Sarah owns a house in Bristol worth £280,000. She buys a new house in Bath for £350,000 on 1 March 2026, intending to make it her main home. She pays the additional property SDLT (£17,500 instead of £5,000). She sells her Bristol house on 1 August 2026. Sarah can claim a £12,500 refund because she sold within 36 months and the Bath house is now her only home.

2. First-time buyers

If you've never owned a residential property anywhere in the world, you're a first-time buyer and the surcharge doesn't apply. You may also qualify for first-time buyer relief (no SDLT on the first £425,000 if the property costs up to £625,000).

3. Properties worth less than £40,000

If your existing property is worth less than £40,000, it's ignored for surcharge purposes. This is rare but can apply to some shared ownership properties or properties in very poor condition.

4. Separated couples

If you're separated from your spouse or civil partner and you've lived apart for at least three years, you're treated as separate buyers. If you're buying a new main home and your ex-partner keeps the old one, you won't pay the surcharge.

5. Inherited property

If you inherit a property, you don't pay SDLT on the inheritance itself. But if you then buy another property while still owning the inherited one, the surcharge will apply to your purchase.

6. Caravans and mobile homes

Static caravans and mobile homes that aren't suitable for year-round occupation don't count as residential property for SDLT purposes.

Special rules for non-UK residents

If you're not a UK resident for tax purposes, you pay an additional 2% surcharge on top of everything else. This means:

If you're a non-resident buying your only UK property: standard rates + 2%
If you're a non-resident buying an additional property: standard rates + 5% (additional property) + 2% (non-resident) = up to 19% on the top band

You're a non-resident if you've been present in the UK for fewer than 183 days in the 12 months before the purchase [Finance Act 2003 Sch 9A].

Example: Non-resident buying a second property

Pierre lives in France and owns a flat in Paris. He buys a £400,000 flat in London:

First £250,000: £250,000 × 7% (5% + 2%) = £17,500
Next £150,000: £150,000 × 12% (10% + 2%) = £18,000
Total SDLT: £35,500

A UK resident buying the same property as an additional home would pay £27,500. Pierre pays £8,000 more because he's non-resident.

Companies buying residential property

If a company buys a residential property, different rules apply:

Properties up to £500,000: The company pays the additional property rates (standard rates + 5%) even if it owns no other property
Properties over £500,000: The company pays a flat 15% rate on the entire purchase price (called the Annual Tax on Enveloped Dwellings rate)

The 15% rate is punitive and designed to discourage wealthy individuals from buying expensive homes through companies to avoid tax.

Example: Company buying a £600,000 property

ABC Property Ltd buys a £600,000 house:

Entire £600,000: £600,000 × 15% = £90,000

An individual buying the same property as an additional home would pay £47,500. The company pays nearly double.

Common mistakes

Mistake 1: Thinking the surcharge only applies to buy-to-let The surcharge applies to any additional residential property, even if you're buying it for a family member to live in rent-free or as a holiday home you'll never rent out.

Mistake 2: Forgetting about property owned abroad If you own a property in Spain, France, or anywhere else in the world, it counts. HMRC can check overseas property ownership through international tax information exchange agreements.

Mistake 3: Missing the 36-month deadline If you're replacing your main home but buy before you sell, you must sell the old one within 36 months to get your refund. Missing this deadline by even one day means you lose the refund entirely.

Mistake 4: Not claiming the refund HMRC doesn't automatically refund your surcharge when you sell your old home. You must actively claim it by submitting an amended return. Many people forget and lose thousands of pounds.

Mistake 5: Assuming joint ownership doesn't count Even if you only own 10% of another property jointly with siblings, it still counts as owning a property for surcharge purposes.

Mistake 6: Thinking inherited property doesn't count While you don't pay SDLT when you inherit, the inherited property counts as one you "own" when you next buy. Many people are caught out buying a home while still owning a property they inherited from parents.

Married couples and civil partners

Married couples and civil partners are treated as a single unit for the additional property surcharge. This means:

If either of you owns another property, you both pay the surcharge
If you're buying jointly, you look at properties owned by both of you combined
If you're buying in one name only, you still look at properties owned by both of you

This can create unfairness. If your spouse owns a flat they bought before you married, you'll pay the surcharge when buying your first home together, even though it's your first property purchase.

Example: Married couple buying together

James owns a flat he bought before marriage. His wife Emma has never owned property. They buy a house together for £400,000 to live in. James will sell his flat within 36 months. They must pay the additional property SDLT initially (£27,500) but can claim a refund when James sells his flat, provided the new house becomes their main home.

How to pay and when

You must pay SDLT and file your SDLT return within 14 days of completion. Your solicitor or conveyancer usually handles this for you, calculating the tax and submitting the return online.

If you're claiming the main residence replacement relief (because you're selling your old home within 36 months), you claim the refund later by filing an amended return after you've sold.

What to do next

The additional property surcharge significantly increases the cost of buying a second home or investment property. If you're planning a purchase:

Calculate the true cost including the 5% surcharge—it might change whether the investment makes financial sense
Plan your timing if you're replacing your main home—buying before selling means paying the surcharge upfront and claiming a refund later
Keep evidence of your main residence status and sale dates if you're claiming a refund
Consider your structure if you're a non-resident or buying through a company—the additional charges can be substantial

If you have specific questions about whether the surcharge applies to your situation, or you need help calculating your SDLT bill, chat with AI Tax for instant answers. If you're completing a property purchase and want an expert to handle your SDLT return and ensure you're not overpaying, AI Accountant can manage the entire process for you, including claiming any refunds you're entitled to.

The surcharge is complex and expensive, but with proper planning, you can minimise the cost and avoid the common pitfalls that catch thousands of buyers every year.

Additional Property SDLT Surcharge (2026)