By Umesh JyaniLast reviewed June 2026
Selling and Buying at the Same Time: Stamp Duty Timing
What happens to your stamp duty bill when you buy before you sell, how chains affect the surcharge, and when you can claim a refund after selling your old home.
Most home movers do not complete on the same day they sell. You buy the new place, pay stamp duty, and hope the old one sells soon after. That gap is where the additional property surcharge catches people.
Why you might pay the surcharge when moving
At completion on your new home, HMRC counts how many residential properties you own. If the old house is still in your name, you own two — so the 5% surcharge applies even though you are replacing your main residence, not buying a buy-to-let.
You pay the higher figure on completion day. Your solicitor includes it in the completion statement.
Getting the surcharge back
If the property you sold was your previous main residence, you can claim a refund of the surcharge after you sell it — provided you sell within 36 months of buying the new home and claim within HMRC’s deadlines.
Full details: Stamp duty refund: the 36-month rule.
How much is at stake
On a £350,000 purchase:
- SDLT as only home: £7,500
- SDLT owning two homes at completion: £25,000
- Potential refund after selling old home: £17,500
Check your exact price on our stamp duty calculator or the £350,000 breakdown.
Chain delays
If your buyer pulls out and your sale stalls, you still own two properties. The surcharge you paid stays until you sell — and the 36-month clock is running.
Some sellers negotiate completion on the same day for both transactions to avoid the surcharge entirely. That requires aligned chains and willing solicitors — not always possible in busy markets.
Bridging loans do not change SDLT
Borrowing to cover the gap between purchases does not reduce stamp duty. SDLT is calculated on the purchase price and your property count at completion, not how you funded it.
First-time buyers in a chain
First-time buyer relief only applies if every buyer has never owned before. If you are buying with someone who owns a property they are selling, relief may not apply — even if you personally have never owned.
Use our first-time buyer calculator and confirm with your conveyancer.
Scotland and Wales
Replacing a main residence in Scotland or Wales follows different refund processes under LBTT and LTT. Use our Scotland and Wales calculators and check devolved authority guidance.
Work out your stamp duty
Use our free calculators to see the exact bill for your purchase price, including any reliefs or surcharges that apply.