Stamp Duty on a £400,000 House: How Much Will You Pay?

If you are buying a property at £400,000, stamp duty is one of the biggest upfront costs you need to plan for. And unlike some costs that are roughly the same for everyone, stamp duty at this price point varies quite dramatically depending on who you are as a buyer.

A first time buyer, an existing homeowner, and someone purchasing a second home can all pay completely different amounts on the exact same £400,000 house. The gap between the cheapest and most expensive scenario at this price is £25,000, which is not a figure you want to discover by surprise on completion day.

This guide walks through every buyer type clearly, shows you the exact calculation for each one, and explains the real-world implications of those figures. All rates apply to completions in England and Northern Ireland under the rules in force from April 2025 onwards. Scotland and Wales operate their own separate property transaction taxes.

If you want an instant figure based on your own situation, use the Stamp Duty Calculator for England to get a full breakdown in seconds. If you are buying in Scotland or Wales, check out the Property Transfer Tax guide for details on how those systems work.

What Is Stamp Duty?

Stamp Duty Land Tax, usually shortened to SDLT or just stamp duty, is a tax paid to HMRC when you buy a property or land in England or Northern Ireland. It applies to freehold and leasehold purchases alike, and it is always the buyer who pays it. The seller has no stamp duty liability.

The tax is calculated in tiered bands, similar to the way income tax works. You do not pay the same percentage on every pound of the purchase price. Instead, different rates apply to different portions of the price as it moves through each band. Only the amount that sits within each band gets taxed at that band's rate.

Stamp duty is a cash payment. It must be paid within 14 days of completion and cannot be added to your mortgage. Your solicitor handles the filing and payment as part of the conveyancing process, but the money needs to be in their client account before completion day.

Does Everyone Pay the Same Stamp Duty on a £400,000 House?

No, and the differences at this price are significant. Here is a quick summary before we go into the full calculations:

First time buyer: £5,000 Existing homeowner moving house: £10,000 Second home buyer: £30,000 Buy to let investor: £30,000

That is a range of £5,000 to £30,000 on the identical property. Knowing which category you sit in before you start making offers is essential, not optional.

Stamp Duty on a £400,000 House for First Time Buyers

First time buyers get a generous helping of relief on properties up to £500,000. The nil-rate threshold for first time buyers is £300,000, which means the first £300,000 of any qualifying purchase is completely exempt. Above £300,000, a 5% rate applies on the portion between the threshold and £500,000.

On a £400,000 house, the calculation for a first time buyer is:

£0 to £300,000 at 0% = £0
£300,001 to £400,000 at 5% = £5,000
Total stamp duty: £5,000

To qualify as a first time buyer for SDLT purposes you must never have owned a residential property before, anywhere in the world. The property must be your main residence. And if you are buying jointly, every single buyer on the transaction must be a first time buyer. If one of you has previously owned a property, the relief disappears for everyone on the purchase.

It is also worth noting that before April 2025, the temporary first time buyer threshold was £425,000, which meant a first time buyer purchasing at £400,000 would have paid nothing at all. Those rules ended on 31 March 2025. Under the current rules, the £5,000 bill applies to all completions from 1 April 2025 onwards.

Stamp duty as a first time buyer on a £400,000 house: £5,000

Stamp Duty on a £400,000 House for Existing Homeowners

An existing homeowner who is selling their current property and buying a new £400,000 home as their main residence pays standard residential rates. No surcharge applies because they are replacing rather than adding to their property ownership.

The calculation works across three bands:

£0 to £125,000 at 0% = £0
£125,001 to £250,000 at 2% = £2,500
£250,001 to £400,000 at 5% = £7,500
Total stamp duty: £10,000

This is double what a first time buyer pays on the same property, which reflects the fact that first time buyer relief is specifically designed to help people get onto the ladder for the first time.

To put this in context, before April 2025 the same home mover would have paid £7,500 on a £400,000 property because the nil-rate threshold sat at £250,000 rather than £125,000. The April 2025 changes added £2,500 to the bill for home movers at this price point.

Stamp duty as a home mover on a £400,000 house: £10,000

One important scenario to be aware of: if you complete on your new £400,000 home before your existing property has sold, HMRC treats you as briefly owning two properties and charges the additional dwelling rates instead of the standard rate. That would push your bill significantly higher. However, if you sell your previous home within 36 months, you can reclaim the additional surcharge. Read the Stamp Duty Refund Guide to understand exactly how that process works and what deadlines apply.

Stamp Duty on a £400,000 House for Second Home Buyers

If you already own a property and are buying a second home rather than replacing your main residence, the additional dwelling surcharge of 5% applies on top of the standard rates across every single band. This surcharge was raised from 3% to 5% in October 2024 and currently shows no sign of changing.

The combined rates for a second home buyer are:

Up to £125,000: 0% standard plus 5% surcharge = 5%
£125,001 to £250,000: 2% standard plus 5% surcharge = 7%
£250,001 to £925,000: 5% standard plus 5% surcharge = 10%

The calculation on a £400,000 second home:

£0 to £125,000 at 5% = £6,250
£125,001 to £250,000 at 7% = £8,750
£250,001 to £400,000 at 10% = £15,000
Total stamp duty: £30,000

The gap between the home mover figure of £10,000 and the second home buyer figure of £30,000 is £20,000. That is the cost of the additional dwelling surcharge across the full purchase price, calculated as 5% of £400,000.

Stamp duty as a second home buyer on a £400,000 house: £30,000

Stamp Duty on a £400,000 Buy to Let Property

Buy to let stamp duty is calculated using exactly the same rates as a second home purchase. You are buying an additional residential property while already owning at least one other, so the 5% surcharge applies throughout.

The calculation is identical:

£0 to £125,000 at 5% = £6,250
£125,001 to £250,000 at 7% = £8,750
£250,001 to £400,000 at 10% = £15,000
Total stamp duty: £30,000

For a property investor, this £30,000 needs to be treated as a day-one cash cost in your investment calculations. On a standard 25% buy to let deposit for a £400,000 property, you are already committing £100,000 in cash for the deposit alone. Add the £30,000 stamp duty, plus legal fees, survey costs, and any work before a tenant moves in, and the total cash required for a single £400,000 rental property can easily reach £135,000 to £140,000.

Investors who calculate rental yield purely on the purchase price, without factoring in all acquisition costs, will consistently overestimate their returns. The stamp duty on a £400,000 buy to let alone reduces an apparent 6% gross yield to something closer to 5.3% when calculated on the true money deployed.

Stamp duty on a £400,000 buy to let property: £30,000

Real World Buying Scenarios

Putting the numbers into real contexts helps illustrate what these figures mean in practice.

Scenario one: First time buyer couple purchasing a new build flat Aisha and James are buying their first home together at £400,000 in the South East. Neither has ever owned property before. Their stamp duty bill is £5,000. They had provisionally budgeted £10,000 because a friend told them they would pay the same as a home mover, so discovering the correct figure frees up £5,000 for furnishing the new flat.

Scenario two: Family trading up from a smaller property The Patels are selling their £250,000 terraced house and buying a £400,000 semi-detached with more space for their growing family. They complete on the sale and the purchase on the same day, so they are only ever owners of one property. Standard rates apply and their stamp duty is £10,000. They factor this into the net proceeds from their sale when planning the move.

Scenario three: Home mover caught in an overlapping chain David finds a £400,000 house he wants but cannot coordinate the sale of his flat to happen on the same day. He completes on the new house two months before his flat sells. At completion, he technically owns two properties and pays the additional dwelling rates of £30,000 instead of £10,000. He is aware of this from the outset and claims a full refund of the £20,000 surcharge nine weeks later when his flat sale completes. For more on this process, including the deadlines involved, see the Stamp Duty Refund Guide.

Scenario four: Landlord adding to an existing portfolio Sarah already owns three rental properties and is buying a fourth at £400,000. The additional dwelling surcharge applies to every further residential purchase in her portfolio. Her stamp duty bill is £30,000, and this is one of the key figures she models before deciding whether the property offers sufficient return.

Other Costs of Buying a £400,000 Home

Stamp duty is the largest single tax cost, but buyers who focus only on this one figure often find themselves underprepared when the other costs arrive.

Solicitor and conveyancing fees for a residential purchase at this level typically run between £1,500 and £2,500. Leasehold properties cost more to convey than freehold because of the additional legal work involved. Get quotes from multiple solicitors and check what is included before you instruct.

Mortgage arrangement fees vary significantly between lenders. Some charge a flat fee of £500 to £1,500, some charge a percentage of the loan, and some offer fee-free products at a slightly higher rate. On a £400,000 purchase you might have a mortgage of £280,000 to £320,000 depending on your deposit, so a percentage-based fee can be meaningful.

Survey costs at this price level are worth spending properly. A full building survey on a property around this value typically costs between £700 and £1,200 depending on the surveyor and the property's age. A homebuyer's report is a middle option at roughly £500 to £800. Skipping a survey to save money is a risk that can prove very expensive if structural issues emerge after completion.

Removal costs depend on distance and volume. A standard family move from one house to another within the same region might cost £800 to £2,000. Cross-country moves or properties with a lot of contents can cost more.

Initial property costs after moving in are easy to underestimate. Most properties need some level of redecoration, new appliances, or minor repairs when you first move in, even if they were well presented at the point of sale.

A realistic summary of total acquisition costs for a home mover buying a £400,000 property might look like this. Stamp duty at £10,000. Solicitor fees at £2,000. Survey at £800. Mortgage arrangement fee at £1,000. Removals at £1,200. Initial property costs at £2,000 or more. The total cash requirement above and beyond your deposit is likely in the region of £17,000 to £20,000.

You can use the Stamp Duty Calculator for England to confirm your stamp duty figure, then build the rest of your acquisition costs around it.

Common Mistakes Buyers Make

Using figures from before April 2025. The temporary nil-rate thresholds that had been in place since September 2022 ended on 31 March 2025. A home mover who looked up their stamp duty before that date and saw £7,500 will now owe £10,000. Always check with a current calculator before budgeting.

Assuming first time buyer status without checking thoroughly. Overseas property ownership, inherited shares in a property, or previously owning jointly with an ex-partner can all disqualify you from the relief. Do not assume you qualify without checking your full ownership history.

Not checking that both buyers qualify on a joint purchase. On a joint purchase, the relief only applies if every named buyer qualifies as a first time buyer. One previous owner on the transaction removes the relief for everyone.

Forgetting stamp duty is a cash payment. This surprises some buyers who assume it can be bundled into the mortgage. It cannot. The funds need to be separate from your deposit and available at completion.

Not accounting for the surcharge on overlapping transactions. Home movers who buy before they sell will initially pay the second home rate. This is avoidable with careful transaction planning, and any surcharge paid can be reclaimed within the deadline. But buyers who are not aware of it at all can be caught completely off guard at completion.

Ignoring total acquisition costs when calculating affordability. Stamp duty plus fees plus moving costs at a £400,000 purchase can add up to £17,000 to £20,000 on top of the deposit. Buyers who budget only for the deposit find themselves short when completion approaches.

Frequently Asked Questions

How much stamp duty does a first time buyer pay on a £400,000 house?

A first time buyer pays £5,000 in stamp duty on a £400,000 house. The first £300,000 is exempt under first time buyer relief and 5% applies to the £100,000 above that threshold.

What is the stamp duty on a £400,000 house for a home mover?

An existing homeowner moving to a £400,000 property as their main residence pays £10,000 in stamp duty. The calculation is 0% on the first £125,000, 2% on the next £125,000, and 5% on the remaining £150,000.

How much stamp duty on a £400,000 buy to let?

A buy to let investor pays £30,000 in stamp duty on a £400,000 property. The 5% additional dwelling surcharge applies on top of the standard rates at every band, resulting in combined rates of 5%, 7%, and 10% across the three relevant bands.

What happens if I pay the second home rate by mistake on a main residence purchase?

If you paid the additional dwelling surcharge because you owned two properties at completion, but then sold your previous main residence within 36 months, you can reclaim the surcharge from HMRC. The refund must be claimed within 12 months of the sale of your old home. Read the Stamp Duty Refund Guide for the full process and eligibility rules.

Can stamp duty be added to my mortgage?

No. Stamp duty is a separate cash payment due within 14 days of completion. It cannot be borrowed as part of a residential or buy to let mortgage and needs to be budgeted for independently alongside your deposit.

Does stamp duty apply the same way in Scotland and Wales?

No. Scotland uses Land and Buildings Transaction Tax and Wales uses Land Transaction Tax. Both have different thresholds, band structures, and rates from England and Northern Ireland. If you are buying in either nation, the figures in this article do not apply. Visit the Property Transfer Tax guide for an overview of how the different systems compare.

Work Out Your Exact Figure With a Stamp Duty Calculator

Every buyer's situation is slightly different, and the fastest way to confirm your exact stamp duty on a £400,000 house is to run it yourself with an up-to-date calculator. A good calculator takes your purchase price, buyer type, and country, and shows you the full band-by-band breakdown in seconds.

Use the Stamp Duty Calculator for England now before you make an offer. Getting your figure right at the research stage means your overall budget is honest from day one, with no surprises waiting for you at completion.

Conclusion

Stamp duty on a £400,000 house ranges from £5,000 for a qualifying first time buyer to £30,000 for a second home buyer or buy to let investor. Home movers sit at £10,000 in the middle, paying standard residential rates without either the benefit of first time buyer relief or the burden of the additional dwelling surcharge.

The April 2025 rule changes made this a more expensive price point than it was in previous years, particularly for first time buyers who previously would have paid nothing on a £400,000 property. Understanding the current rules rather than relying on older information is essential for accurate budgeting.

Beyond stamp duty, the total upfront cash requirement for a £400,000 purchase can add £17,000 to £20,000 on top of your deposit when you account for all acquisition costs. Plan for the full picture, confirm your stamp duty with a calculator, and make sure the funds are available and ready before your completion date.

References

HM Revenue and Customs (2025). Stamp Duty Land Tax. GOV.UK. Available at: https://www.gov.uk/stamp-duty-land-tax

HM Revenue and Customs (2025). Stamp Duty Land Tax: higher rates for additional dwellings. GOV.UK. Available at: https://www.gov.uk/guidance/sdlt-higher-rates-for-additional-dwellings

NatWest (2026). Stamp Duty Changes: April 2025. Available at: https://www.natwest.com/mortgages/mortgage-guides/stamp-duty-introduction/stamp-duty-changes.html

MoneySavingExpert (2026). Stamp Duty Calculator 2026: How much and when to pay it. Available at: https://www.moneysavingexpert.com/mortgages/stamp-duty/

My Home Move Conveyancing (2026). Stamp Duty Changes: 2025 and 2026. Available at: https://myhomemoveconveyancing.co.uk/buyers/what-can-you-afford/stamp-duty-changes-2025/

Property Investor Today (2026). Stamp Duty Rates in 2026. Available at: https://www.propertyinvestortoday.co.uk/article/2025/11/stamp-duty-rates-in-2026/

KIS Bridging Loans (2025). Stamp Duty Calculator 2026. Available at: https://www.kisbridgingloans.co.uk/stamp-duty-calculator/

Fox Davidson (2026). Residential Stamp Duty Calculator 2026. Available at: https://www.foxdavidson.co.uk/calculators/residential-property-stamp-duty-calculator-2025/