Stamp Duty Calculator

Stamp Duty Land Tax (SDLT) is a tax payable when you purchase property or land in England and Northern Ireland above certain price thresholds. It is one of the largest upfront costs of buying a home, and understanding how it is calculated can help you budget accurately and identify any reliefs you may be entitled to. Scotland and Wales have their own equivalent taxes (LBTT and LTT respectively), which operate under different rates and rules.

How SDLT Is Calculated: Progressive Bands

SDLT works on a progressive (or “slice”) system, similar to income tax. You only pay the higher rate on the portion of the purchase price that falls within each band, not on the entire amount. For example, if you purchase a property for £300,000 as a home mover in 2025/26, you pay 0% on the first £125,000, 2% on the next £125,000 (£2,500), and 5% on the final £50,000 (£2,500), giving a total SDLT of £5,000. This progressive structure means the effective rate is always lower than the headline rate for the highest band your purchase falls into.

First-Time Buyer Relief

First-time buyers benefit from enhanced nil-rate thresholds. For purchases up to £300,000, no SDLT is payable at all. For purchases between £300,001 and £500,000, the first £300,000 is tax-free and 5% applies to the remainder. However, if the purchase price exceeds £500,000, first-time buyer relief is lost entirely and standard home mover rates apply to the full amount. This cliff-edge means a first-time buyer purchasing at £500,000 pays £10,000, while one purchasing at £500,001 pays £12,500 -- a £2,500 jump for just £1 more in purchase price. Careful negotiation of the purchase price near this threshold can yield significant savings.

Additional Property Surcharge

If you are purchasing a second home, buy-to-let investment property, or any additional residential property while still owning another, a 5% surcharge applies on top of the standard SDLT rates across all bands. This means the first £125,000 is taxed at 5% rather than 0%, and higher bands increase correspondingly. The surcharge applies even if the property being purchased is of lower value than your main residence. However, if you are replacing your main residence (selling your old home and buying a new one), the surcharge does not apply. If you purchase the new home before selling the old one, you pay the surcharge upfront but can claim a refund within three years once the previous main residence is sold.

SDLT on Commercial and Mixed-Use Property

Commercial property and mixed-use property (properties that combine residential and non-residential elements) are subject to different SDLT rates. The first £150,000 is charged at 0%, the next £100,000 (up to £250,000) at 2%, and everything above £250,000 at 5%. These rates are significantly lower than residential rates at higher price points, which is why mixed-use classification can be advantageous. A property with a genuine commercial element -- such as a flat above a shop, or a farmhouse with agricultural land -- may qualify for mixed-use treatment, potentially saving tens of thousands of pounds in SDLT. Professional tax advice is essential to ensure the correct classification is applied.

Transfers Between Spouses and Civil Partners

Transfers of property between spouses or civil partners who are living together are generally exempt from SDLT, provided there is no outstanding mortgage being assumed. If there is a mortgage, SDLT may be due on the value of the mortgage transferred. This exemption also applies on divorce or dissolution, regardless of whether the couple is still living together. However, transfers between unmarried partners do not qualify for this exemption and are treated as standard transactions, potentially triggering a full SDLT charge including the additional property surcharge.

When SDLT Must Be Paid

SDLT is due within 14 days of completion (the date when legal ownership transfers). Your solicitor or conveyancer typically handles the SDLT return and payment as part of the conveyancing process, but the legal liability rests with the buyer. Late filing and late payment both incur automatic penalties and interest. For complex transactions involving tax planning considerations -- such as purchases through companies, transfers of development land, or transactions involving connected parties -- seeking specialist advice before exchange of contracts is strongly recommended to avoid unexpected liabilities.