Stamp Duty Calculator
Stamp Duty Land Tax applies to property purchases in England and Northern Ireland, calculated in bands that rise as the price increases, with separate rules for first-time buyers and an additional surcharge for second homes or buy-to-let purchases. This calculator works out exactly what you would owe based on the purchase price and your buyer status.
Stamp Duty Calculator
Calculate Stamp Duty Land Tax (SDLT) on your property purchase for 2026/27.
The Surcharge Just Went Up — And It’s Not Small
The additional property surcharge, applying to second homes and buy-to-let purchases, was raised from 3% to 5% in October 2024, a genuinely significant increase worth being aware of if you are working from information published before that change took effect. This calculator uses the current, correct 5% rate — on a typical property purchase, this increase alone adds thousands of pounds compared with the previous rate, which is worth factoring clearly into the real cost of an additional property purchase.
This is worth double-checking specifically if you have seen an older article, a previous quote, or a rough mental estimate based on the earlier 3% figure — the 2 percentage point increase applies to the entire purchase price, not a small technical adjustment, and meaningfully changes the true cost of proceeding with a second property or buy-to-let purchase.
Why £500,001 Is a Genuine Cliff Edge for First-Time Buyers
First-time buyer relief provides 0% SDLT on the first £300,000 of a purchase price, with 5% charged on the portion between £300,000 and £500,000 — but this relief is not gradually reduced above £500,000; it disappears entirely, with standard rates applying to the full price instead. This creates a genuine cliff edge exactly at this threshold: a £500,000 purchase for a first-time buyer costs £10,000 in SDLT, but a £500,001 purchase — just £1 more — costs roughly £15,000 instead, since the relief is withdrawn completely rather than tapering away gradually. This is worth knowing clearly if a purchase price is close to this specific threshold, since a small negotiation difference either side of £500,000 can have a genuinely disproportionate effect on the total SDLT bill.
This is genuinely worth raising directly during price negotiation if an offer is hovering close to £500,000 — a buyer and seller agreeing to settle at exactly £500,000 rather than a few hundred or thousand pounds above it can make a considerably larger practical difference to the buyer’s total cost than the headline price difference alone would suggest.
The Surcharge Applies to the Whole Price, Not Just the Extra
The additional property surcharge is calculated as 5% of the entire purchase price, added on top of the standard banded SDLT calculation — not 5% applied only to the amount above a specific threshold. A £300,000 additional property purchase, for example, produces roughly £5,000 in standard banded SDLT plus a further £15,000 in surcharge, for a combined total of roughly £20,000 — the surcharge portion alone is considerably larger than the standard SDLT on the same purchase, precisely because it applies to the full price rather than being tucked into the existing band structure.
This flat, whole-price structure is precisely why the surcharge scales up so directly with the size of the purchase — unlike the standard bands, which only tax higher portions of the price at higher rates, the surcharge applies its full percentage uniformly from the very first pound of the purchase price.
Working Out What You’ll Actually Owe
The effective rate this calculator shows — total SDLT as a percentage of the purchase price — is a useful, quick way to sense-check a specific figure against the purchase price, since the banded structure means the effective rate is always lower than the top marginal rate that applies to only the final portion of the price. Checking your buyer status carefully before relying on a specific figure matters considerably, since first-time buyer relief and the additional property surcharge both meaningfully change the outcome compared with a standard purchase. Our Mortgage Deposit Calculator is useful for planning the deposit side of a purchase alongside the SDLT cost this calculator works out, and our Landlord Insurance Calculator is worth checking if you are specifically purchasing a buy-to-let property subject to the additional property surcharge.
Frequently Asked Questions
Does Scotland or Wales use the same SDLT rates?
No — Scotland uses Land and Buildings Transaction Tax and Wales uses Land Transaction Tax, both with genuinely different bands and rates from SDLT, so this calculator’s figures apply specifically to property in England and Northern Ireland.
Who counts as a first-time buyer for SDLT purposes?
Generally someone who has never owned a residential property anywhere in the world before, including overseas, and who intends the new purchase to be their only or main residence — owning a share in a previous property can affect eligibility even if the current purchase is genuinely your first home in the UK.
Do I pay the surcharge if I am replacing my main residence?
Generally not, provided you sell your previous main residence within a set window around the new purchase — the surcharge is specifically aimed at additional properties kept alongside an existing main residence, not a genuine like-for-like replacement of your only home.
When is SDLT actually due?
SDLT must be paid, and a return filed, within 14 days of completing the purchase, which is typically handled by your solicitor or conveyancer as part of the completion process rather than something you need to arrange directly yourself.
Does SDLT apply to the full price or just the amount financed by a mortgage?
SDLT is calculated on the full purchase price of the property, regardless of how much of that price is covered by a mortgage versus a cash deposit, so the calculation is unaffected by your specific financing arrangement.
Important Information
This calculator provides an estimate based on current 2026/27 SDLT rates for general information purposes only and does not constitute tax or legal advice. Rules can change and individual circumstances vary. For advice specific to your purchase, consult a solicitor or conveyancer. See our Disclaimer for further information.