Buy to Let Stamp Duty Calculator UK 2025/26

Reviewed by Mustafa Bilgic
UK Calculator Editor · Updated May 2026

BTL SDLT bands and the 5% surcharge

From 31 October 2024 the Additional Dwelling Surcharge increased from 3% to 5%. It applies to anyone buying a residential property in England or Northern Ireland while already owning at least one dwelling anywhere in the world worth more than £40,000. This includes BTL purchases, second homes, holiday lets, and inherited properties bought subsequently.

The 5% surcharge sits on top of the entire purchase price (sliced bands not applicable). On a £400,000 BTL the standard SDLT is £7,500 (0% on £250k + 5% on £150k slice) and the surcharge is £20,000 (5% × £400k). Total: £27,500 — an effective rate of 6.88%.

Reclaiming the surcharge if you sell your main home

If you bought a new main residence before selling the old one (so were temporarily a multi-home owner), you can reclaim the 5% surcharge if you sell the previous main residence within 36 months of the new purchase. The application is via HMRC online — it must be made within 12 months of the sale or within 12 months of the SDLT return filing deadline, whichever is later.

The reclaim does not apply to genuine second homes or BTLs — only to residences temporarily held while moving home. For a BTL, the surcharge is a permanent cost.

Entry-level £150,000 BTL

Standard SDLT: £0 (below £250k threshold). Surcharge: 5% × £150,000 = £7,500. Total: £7,500. Effective rate 5.00%.

Mid-range £400,000 BTL

Standard: 5% × £150,000 above the £250k threshold = £7,500. Surcharge: 5% × £400,000 = £20,000. Total: £27,500. Effective rate 6.88%.

£750,000 BTL in London commuter belt

Standard: 5% × £675,000 = £33,750. Surcharge: 5% × £750,000 = £37,500. Total: £71,250. Effective 9.50%. SDLT alone equals 6 months gross rent at typical 5% yield.

Common mistakes to avoid

• Forgetting that overseas property counts toward 'already owns a dwelling' — a flat in Mumbai triggers the surcharge on a Bristol BTL.
• Believing that owning through a sibling or trust avoids the surcharge — beneficial ownership tests apply.
• Missing the 14-day filing window after completion — penalties accrue immediately.
• Treating mixed-use (shop with flat above) as residential SDLT — non-residential SDLT applies and the surcharge does not.
• Assuming gifts or inheritance escape the surcharge — both can trigger it on a subsequent purchase.

When to use this calculator

Use before signing a BTL offer, when the surcharge can be material to the deal economics. Run again at remortgage to reassess gross-yield versus net after every cost.

How this differs in Scotland, Wales and Northern Ireland

England and NI use SDLT with the 5% surcharge. Scotland uses LBTT with an 8% Additional Dwelling Supplement (raised from 6% in December 2024). Wales uses LTT with a 5% surcharge. The percentages differ but the principle — purchase tax penalty for BTL — applies across the UK.

When this calculator is and isn't the right tool

The Buy to Let Stamp Duty Calculator UK 2025/26 above is built for the most common UK 2025/26 scenarios in this tax area. It will be the right tool when your situation maps cleanly onto the inputs — single property or simple aggregation, standard HMRC rates and bands, and individual taxpayer (rather than complex trust or partnership structures). It is informational and does not replace tailored advice from a chartered tax adviser, especially for transactions above £500,000, cross-border situations, or where reliefs interact with each other. For year-end filings, always reconcile with HMRC's own free calculators on gov.uk before pressing submit on Self Assessment.

Closely related calculators

• Buy to Let Stamp Duty (legacy) — useful when you need a different angle on the same UK property tax topic, especially if your situation involves multiple types of property income or disposal.
• Second Home Stamp Duty 2026 — useful when you need a different angle on the same UK property tax topic, especially if your situation involves multiple types of property income or disposal.
• Additional Property SDLT — useful when you need a different angle on the same UK property tax topic, especially if your situation involves multiple types of property income or disposal.
• Non-UK Resident SDLT — useful when you need a different angle on the same UK property tax topic, especially if your situation involves multiple types of property income or disposal.
• Landlord Tax Calculator — useful when you need a different angle on the same UK property tax topic, especially if your situation involves multiple types of property income or disposal.

Glossary of UK property tax terms

SDLT

Stamp Duty Land Tax — the UK government tax on residential property purchases in England and Northern Ireland.

HRAD

Higher Rates for Additional Dwellings — the formal name for the 5% surcharge on second homes and BTL purchases.

SDLT1

The HMRC return form filed within 14 days of completion to declare and pay SDLT.

Sliced bands

SDLT is charged on slices of the price within each band, not on the whole price at the highest band.

Effective rate

Total SDLT divided by the purchase price, expressed as a percentage.

Tax planning checklist

1. Confirm the figures input above match your actual position — purchase contract, mortgage offer or completion statement.
2. Cross-check the year (2025/26) — figures change every April. The tax year 2026/27 starts 6 April 2026.
3. Use HMRC's official calculator at gov.uk for the final filing figure; this calculator is informational.
4. Keep records for at least 6 years — HMRC's normal enquiry window. 21 years for fraud investigations.
5. Discuss any unusual transaction (joint purchase, gift, divorce settlement, trust) with a qualified tax adviser.
6. Submit your return online via Government Gateway — paper deadlines are earlier and penalties harsher.