Methodology and Sources
How every rate figure on this site is sourced and computed. Three statutory regimes (SDLT, LBTT, LTT) each have one primary source published by the relevant tax authority. The calculation framework is documented per band, with the marginal math shown on screen for every result.
Sources verified May 2026
Primary statutory sources
Every rate figure on the site traces to one of these sources. The methodology is: one regime, one source per regime, math shown on page.
| Regime | Source | What we take from it |
|---|---|---|
| SDLT (England + NI) | HMRC, Stamp Duty Land Tax overview | Top-level SDLT entry-point including rules on who pays, when payment is due and the SDLT1 return. |
| SDLT (England + NI) | HMRC, SDLT residential property rates | Canonical residential SDLT band table. Bands: 0% to £125k, 2% to £250k, 5% to £925k, 10% to £1.5m, 12% above. |
| SDLT (England + NI) | HMRC, SDLT non-residential property rates | Commercial / non-residential band table. Bands: 0% to £150k, 2% to £250k, 5% above. Different rules for mixed-use. |
| SDLT (England + NI) | HMRC, higher rates on additional dwellings (5% surcharge) | Statutory framework for the 5% additional-property surcharge introduced October 2024 (up from the previous 3%). |
| SDLT (England + NI) | HMRC, first-time buyer relief | Statutory note governing the first-time buyer nil-rate (£300k from April 2025) and the £500k cliff above which the relief is lost entirely. |
| SDLT (England + NI) | HMRC, non-UK resident SDLT surcharge | Statutory framework for the 2% non-UK-resident surcharge, the 183-day residence test and the refund route within 2 years of purchase. |
| LBTT (Scotland) | Revenue Scotland, Land and Buildings Transaction Tax | Canonical LBTT band entry-point. Bands: 0% to £145k, 2% to £250k, 5% to £325k, 10% to £750k, 12% above. |
| LBTT (Scotland) | Revenue Scotland, Additional Dwelling Supplement (ADS) | ADS is 8% charged on the full purchase price (not marginal). Structural difference vs England's 5% marginal surcharge. |
| LTT (Wales) | Welsh Government, Land Transaction Tax guide | Top-level LTT entry-point including filing rules, the WRA portal and applicable bands. |
| LTT (Wales) | Welsh Government, LTT higher rates for additional residential property | Banded higher-rate structure introduced December 2024. Unlike England, Wales does not apply a flat surcharge on top of standard bands; it has its own marginal banded structure for additional properties. |
| Statute (England + NI) | legislation.gov.uk, Finance Act 2003 (root SDLT statute) | The original statutory basis for SDLT. Subsequent Finance Acts (most recently Spring Budget 2024 / Autumn Budget 2024) amend specific bands and thresholds. |
| Statute (Scotland) | legislation.gov.uk, Land and Buildings Transaction Tax (Scotland) Act 2013 | The statutory basis for LBTT. The Scottish Budget amends bands by Order each year. |
| Statute (Wales) | legislation.gov.uk, Land Transaction Tax (Wales) Act 2017 | The statutory basis for LTT. The Welsh Senedd budget amends bands and the higher-rate structure. |
| Budget | HM Treasury, Spring Budget 2024 | The Budget that confirmed the additional-property surcharge increase from 3% to 5% and the abolition of Multiple Dwellings Relief. |
| Budget | HM Treasury, Autumn Budget 2024 | Budget package confirming the SDLT threshold reversion taking effect from 1 April 2025: standard nil-rate £250,000 to £125,000, first-time buyer nil-rate £425,000 to £300,000, first-time buyer cliff £625,000 to £500,000. |
Calculation framework
SDLT marginal band math
SDLT is computed band-by-band. Each band rate applies only to the portion of the price falling within that band. Example for a £400,000 standard purchase in 2026: 0% on £0 to £125,000 (£0) + 2% on £125,000 to £250,000 (£2,500) + 5% on £250,000 to £400,000 (£7,500) = £10,000. The calculator shows this breakdown on screen for every result.
First-time buyer relief and the £500k cliff
First-time buyer SDLT replaces the standard band schedule with 0% to £300,000 then 5% on £300,000 to £500,000. If the purchase price is above £500,000 the relief is lost entirely (the cliff) and the standard band schedule applies to the full price. The calculator applies the cliff automatically.
Additional property 5% surcharge (England + NI)
The 5% surcharge applies on top of every band including the nil-rate band. Bands become 5%, 7%, 10%, 15%, 17%. Applied marginally. Refund route under the replacing-main-residence test if the previous main residence is sold within 3 years and the refund is claimed within 12 months of that sale.
Non-UK resident 2% surcharge (England + NI)
The 2% surcharge stacks on top of every other applicable rate. A non-UK resident buying a second home pays standard + 5% + 2% = 7% on top of every band. Refund route if the buyer satisfies the 183-day residence test within 2 years of purchase.
Scotland LBTT and ADS structural difference
LBTT bands are marginal like SDLT but the Additional Dwelling Supplement (ADS) is charged at 8% on the full purchase price, not marginally. A £200,000 second home in Scotland pays £1,100 LBTT + £16,000 ADS = £17,100 total. The same £200,000 second home in England pays £11,500 SDLT (with the 5% surcharge applied marginally). Scotland's structure is materially more punishing for additional properties at low to mid prices.
Wales LTT banded higher rates (December 2024 reform)
Wales does not apply a flat surcharge on top of standard bands. The higher-rate structure for additional properties is its own marginal band schedule starting at 5% from £0 to £180,000 and topping out at 17% above £1.5m. The structure was reformed in December 2024; the calculator and /wales page apply the post-reform bands.
In scope
- +SDLT bands and rates for England and Northern Ireland (residential, post-April-2025 thresholds)
- +First-time buyer relief and the £500,000 cliff edge
- +Additional property 5% surcharge with replacing-main-residence refund route
- +Non-UK resident 2% surcharge with 183-day residence test refund route
- +LBTT bands for Scotland including ADS at 8% on full price
- +LTT bands for Wales including the December 2024 banded higher-rate reform
Out of scope
- -Bespoke conveyancing fees and solicitor pricing (see sister site SolicitorCost.com)
- -Mortgage pre-approval and affordability calculations (see MortgagePreApprovalCalculator.com)
- -Land Registry registration fees (HM Land Registry maintains the canonical fee schedule)
- -Capital gains tax on residential property (HMRC CGT publications)
- -Inheritance tax thresholds and reliefs (HMRC IHT publications)
- -Commercial / non-residential SDLT at depth (rate-table reference only; advisers should consult HMRC non-residential guidance for complex multi-tenant or six-or-more-dwellings rule cases)
Refresh cadence
The site is reviewed on a monthly first-business-week pass. Every page's LAST_VERIFIED date and the footer label flow from a single constant (LAST_VERIFIED_DATE in src/lib/schema.ts) so the dates cannot drift apart silently. The constant currently reads May 2026.
Out-of-cycle refreshes are triggered by:
- →UK Budget statements (Spring + Autumn) - rolled into the next monthly refresh once Royal Assent / Finance Act is published
- →Scottish Budget - rolled in once the Land and Buildings Transaction Tax (Tax Rates and Tax Bands etc) (Scotland) Order is laid
- →Welsh Senedd budget - rolled in once the LTT bands SI is laid
- →Mid-year emergency Finance Bills (rare)
- →HMRC, Revenue Scotland or WRA publishes a clarification that materially changes how a rule applies
What we deliberately do not publish
Choices about scope that protect the site's editorial independence and statutory accuracy.
- xPer-postcode property price predictions (out of scope; we only publish statutory rates and the band-by-band math)
- xSpecific lender mortgage pre-approval amounts (delegated to MortgagePreApprovalCalculator.com)
- xSpecific solicitor fee quotes (delegated to SolicitorCost.com)
- xAffiliated insurance, ISA, or pension product placements
- xLive property-listing data or estate-agent commission rates
Limitations and corrections
The calculator outputs are estimates derived from published statutory rate tables. They do not capture every exemption (transfer of equity in divorce, charity relief, multiple dwellings rule under the now-abolished MDR transitional period, group relief between connected companies). Always verify your specific transaction with your solicitor or a qualified tax adviser before completion.
Spotted a stale figure or a citation that no longer resolves? Email [email protected] with the URL, the line you would like cited and the source. Corrections are usually made within 5 business days. Statutory updates (Budget, Scottish Budget, Senedd budget) are rolled into the next monthly refresh.
Read next: About StampDutyRate.com for the editorial framework and operator background.