Mortgage question
Do married couples pay the stamp duty surcharge if one of us owns a flat?
Yes — if you are married or in a civil partnership, HMRC treats you as a single unit for stamp duty. That means if either of you owns another residential property worth £40,000 or more (in the UK or overseas), the 5% additional-property surcharge applies to your new home. It doesn’t matter whose name is on the new deed, whose money is paying for it, or whether the other property is rented out, empty, or an inherited holiday flat.
Why does the surcharge apply even if the new home is only in my name?
Because paragraph 9 of Schedule 4ZA of the Finance Act 2003 deems a spouse’s or civil partner’s property interests to be your own for the higher-rates test. So even if you buy a new main home entirely in your sole name, with your own income and your own deposit, HMRC looks at the household — not the legal title — when deciding whether the 5% surcharge bites.
The rule only switches off if you are “permanently separated” in a way that is formal: a court order of separation, a decree of judicial separation, or a deed of separation. Being unhappily married and living apart informally is not enough. If you divorce, you stop being a couple for SDLT from the date of the decree absolute (or final order).
A worked example for April 2026:
- Priya owns a buy-to-let flat in Leeds worth £180,000 that she has had since 2018.
- She marries Alex in 2025. Alex has never owned property.
- In May 2026 they buy a £400,000 house in Alex’s sole name.
Even though Alex is a first-time buyer on paper, Priya’s flat means the couple are treated as already owning a residential property. The purchase is taxed at the higher rates: 5% on the first £250,000, 10% on the next £150,000 — an SDLT bill of £27,500 rather than the £7,500 a standalone FTB would pay. And Alex loses first-time buyer status entirely because of the all-or-nothing FTB rule.
What counts as “another property” for the surcharge test?
Any “major interest” in a dwelling anywhere in the world with a market value of £40,000 or more. That includes:
- A UK buy-to-let in either spouse’s name.
- A holiday home in Spain, Portugal, France, or anywhere else overseas.
- An inherited share of a family home (more than 50% ownership counts, and even a smaller share if inherited more than three years before the new purchase).
- A flat held jointly with family members.
Properties worth less than £40,000 are ignored — HMRC calls this the “minor interests” rule. So a small share of a Scottish croft or a half-derelict overseas farmhouse valued at £25,000 wouldn’t trigger the surcharge.
| Scenario | Partner A owns | Partner B owns | Buying | Surcharge applies? |
|---|---|---|---|---|
| 1 | Nothing | £180k UK BTL | £400k new main home | Yes — 5% surcharge |
| 2 | £35k share of overseas home | Nothing | £350k UK home | No — below £40k |
| 3 | £300k main home (selling same day) | Nothing | £450k new main home | No — replacement of main residence |
| 4 | £500k holiday home in Italy | Nothing | £400k UK main home | Yes — 5% surcharge |
| 5 | Nothing | Nothing | £400k new main home | No — neither owns |
Can we get the money back later?
Yes, if the property you’re keeping is a genuine former main residence and you sell it within 3 years of completion on the new home. You pay the surcharge up-front at completion, then claim it back from HMRC using form SDLT16 or the online reclaim service. The refund typically takes 15–20 working days.
The rule is strict, though. If the “other” property that triggered the surcharge is a buy-to-let or a holiday home (not the home you’ve been living in), you cannot reclaim — the surcharge is permanent. See our companion piece on reclaiming the surcharge after selling your old home for the steps.
Common misconception: “We’ll just buy in my name — surely HMRC won’t know about my partner’s Spanish flat?”
They will. Your conveyancer is required to ask the SDLT surcharge questions as part of the Property Information Form (TA6) and when preparing your SDLT return. Lying on the return is tax fraud, and HMRC routinely cross-references Land Registry data with UK tax records and with overseas property registers under the Common Reporting Standard. Penalties can reach 100% of the tax owed, plus interest.
If you think the surcharge might apply to you, talk to your conveyancer early and run the numbers through our stamp duty calculator before you exchange. Better still, check whether selling the other property first — or electing to treat one home as your main residence under the nomination rules — can keep the bill down.
This is information, not regulated tax advice. Speak to a qualified conveyancer or tax adviser about your own circumstances before completing.
Sources
Information, not regulated advice. Mortgage Notes is not an FCA-authorised mortgage adviser. For a recommendation on your specific circumstances, speak to an FCA-authorised broker.