Editorial standards & corrections

How we verify rates, source facts, and handle corrections

Who is responsible for this site

Stamp Duty Calculator is published by POW XD Ltd, a company registered in the United Kingdom, which is responsible for what is published here, including the calculators, guides and corrections. Pages carry the site name, "Stamp Duty Calculator", as author rather than a named person or specialist.

Our guides are drafted with AI assistance and checked against official sources (GOV.UK, HMRC, HM Land Registry, Revenue Scotland, the Welsh Revenue Authority and legislation.gov.uk) before publishing. Figures are reviewed on the date shown on each page. This is general information, not legal, tax or financial advice.

We do not claim professional qualifications. The site is not run by a solicitor, licensed conveyancer, chartered tax adviser, accountant or FCA-authorised adviser, and its pages are not reviewed by one. That is why we tie every tax figure to a published primary source and test the calculators against HMRC's own worked examples, and why everything here is general information rather than advice.

How we verify rates

SDLT rates and related thresholds are the lifeblood of this site. We verify them against HMRC's published rate tables on GOV.UK every time we update content, and we re-verify the entire calculator's rate tables after every UK Budget, Spring Statement, and any HMRC notice announcing rate changes. The "Rates last verified" date at the bottom of every calculator and rate page reflects the most recent check.

Our sourcing rules

Every factual statement on the site is sourced from primary authorities. We do not source from competitor calculators, property blogs, or aggregator sites. Primary sources we use:

  • GOV.UK — HMRC, HM Treasury, HM Land Registry, Ministry of Housing
  • HMRC internal manuals — SDLT manual, CGT manual, IHT manual
  • legislation.gov.uk — statutory text of Finance Acts and related instruments
  • Bank of England — financial stability publications and mortgage market data
  • Office for National Statistics (ONS) — house price indices, transaction statistics
  • Financial Conduct Authority (FCA) — mortgage market data, conduct of business rules
  • BAILII — tribunal and court judgments on SDLT and tax disputes

Editorial review process

Every article on the site goes through this process before publication:

  1. Drafting. Pages are drafted or updated with AI assistance (Claude, an AI model made by Anthropic). Nothing is copied from other calculators or aggregator sites.
  2. Source check. Every rate, threshold and rule is checked against a primary source linked in the page's "Sources" panel (GOV.UK, HMRC manuals, legislation.gov.uk, Revenue Scotland, the Welsh Revenue Authority, the FCA or the Bank of England).
  3. Calculation verification. Worked examples are recomputed with the site's own calculation engine. The SDLT, LBTT and LTT engines are covered by automated regression tests, including HMRC's published examples (for instance £295,000 = £4,750 for a home mover). Figures quoted in guides are tested against the same engine, so a stale number fails the build.
  4. No professional sign-off. Content is not reviewed by a solicitor or tax adviser. Where a rule depends on facts we can't know (for example whether an annex is a separate dwelling), we say so and suggest getting professional advice.
  5. Plain-language check. Edited for clarity. We avoid jargon where possible; where we use technical terms, we define them.
  6. Publication. "Last verified" date stamped at the bottom.

After publication, every article is re-reviewed at least once a year, or sooner if HMRC publishes a relevant change. Rate-sensitive articles (the calculators, the rates page, the timeline) are re-reviewed after every Budget and Spring Statement.

Corrections policy

We aim to be accurate. When we get something wrong, we correct it and tell you what changed.

  1. Spot an error? Email seo@powxd.co.uk with the page URL and what's wrong. Include a source if you can — it speeds things up.
  2. What we do. We review the report within 3 working days. If the report is valid, we update the page within 7 working days.
  3. How we mark the change. Material corrections (a changed figure, a corrected rule) are noted in the corrections log below. Minor typo fixes are made silently.
  4. If we can't reproduce the error. We'll reply with our reasoning and the source we relied on, and the page stays as it is.

Corrections log

Material changes to figures or rules, newest first. Each entry gives the date, the page, what changed and why.

  • 2 November 2026: bylines and authorship. Pages now carry the site name as author, with a note that guides are drafted with AI assistance and checked against official sources. The previous byline described a team, which implied more people than are involved, so we removed it. The remortgage cashback notes no longer quote typical cashback amounts we could not source.
  • 2 November 2026: Multiple Dwellings Relief calculator. The historic worked example used the post-April-2025 bands. It now uses the rates the calculator applies (£32,500 without MDR at standard rates, not £35,000). The post-abolition example now uses current rates. Corrected the transitional rule ("on or before 6 March 2024"), the legislation reference (Finance (No. 2) Act 2024 section 7, not section 12), the company single rate (17% since 31 October 2024, not 15%) and the claim time limits (amend within 12 months of filing; overpayment relief within 4 years of the effective date). Removed an unsourced "abuse" explanation and advice that splitting contracts avoids the multiple-dwelling rules.
  • 2 November 2026: mortgage stress-test pages. The 3% stress test withdrawn in August 2022 was a Bank of England Financial Policy Committee Recommendation, not an FCA rule. We corrected the attribution and kept the point that the FCA's MCOB affordability rules still apply.
  • 2 November 2026: eight "stamp duty on a £X house" pages. Replaced generic "buyer profile" paragraphs (unsourced claims about areas and property types) with a deposit, mortgage and cash-needed table calculated for each price.
  • 27 October 2026: second-home and surcharge guides. Corrected stale surcharge figures. The surcharge on the second home guide £550,000 example is £27,500. On the selling-the-first-home guide, the £500,000 surcharge is £25,000. The surcharge refund guide table had wrong figures at £400,000 to £900,000. Cause: figures carried over from before the surcharge rose to 5% and the nil-rate band returned to £125,000.
  • 27 October 2026: SDLT rates 2026. Updated the £1m and £1.5m rows to the bands in force from 1 April 2025 (£43,750 and £93,750).
  • 27 October 2026: refund, non-resident, second-home calculator, budget planner and first-time buyer relief pages. Corrected worked examples and FAQ figures to match the calculator. For example, the maximum first-time buyer saving is £5,000.

What we are not

We are not a regulated financial adviser. We are not your solicitor, conveyancer, accountant or mortgage broker. The information on this site is general guidance only and is not a substitute for personalised professional advice. For your specific situation, please speak to an FCA-regulated mortgage broker (for mortgages), a CTA-qualified tax adviser (for tax), or a SRA-regulated solicitor (for conveyancing).

Editorial standards last reviewed: 2 November 2026.