Terms of Service for UK Mortgage & Stamp Duty

Last Updated: 11 July 2026

Developer: Corithm Flow Matrix | Contact: dev@corithmflowmatrix.com

1. Acceptance of Terms

By downloading, installing, or using UK Mortgage & Stamp Duty ("the App"), you agree to these Terms of Service. If you do not agree, do not use the App. You confirm that you are at least 18 years old.

2. What the App Does

UK Mortgage & Stamp Duty is an offline home-buying toolkit for the UK. Features include:

Mortgage repayment calculator (repayment and interest-only) with amortisation schedule
Overpayment calculator (interest saved and term reduced)
Stamp duty: SDLT (England & Northern Ireland), LBTT (Scotland) and LTT (Wales), including first-time-buyer relief and the additional-property surcharge
Affordability, deposit & LTV, total cost of buying, and rent-vs-buy comparison
Extra tools: remortgage compare, offset mortgage, shared ownership, early repayment charge, and overpay-vs-invest

Not affiliated with HMRC or any government body. UK Mortgage & Stamp Duty is an independent third-party tool and is not endorsed by, operated by, or connected to HMRC, GOV.UK, Revenue Scotland, the Welsh Revenue Authority, or any government department. It does not file returns, submit claims, or transmit data to any tax authority.

Estimate only — not financial, mortgage or tax advice. All calculations are estimates based on published rates for the selected tax year and may not reflect your exact circumstances or the offers available to you. Your actual mortgage rate, payments, stamp duty, and eligibility depend on the lender, solicitor and your situation. Always verify figures with a qualified mortgage broker, solicitor, and the official calculators at gov.uk, revenue.scot or gov.wales before making decisions. Corithm Flow Matrix is not liable for any loss arising from reliance on the App.

3. Free and Pro Tiers

Free includes all calculators, saving up to 2 scenarios, and shows ads.

Pro (one-time lifetime purchase) adds unlimited saved scenarios, side-by-side compare, full PDF export (cost summary and amortisation), and removes ads.

4. In-App Purchases

Purchases are processed by Google Play.
Pro is a one-time, lifetime purchase — not a subscription.
Purchases are non-refundable except where required by law.
Pro can be restored on reinstall via Google Play.

5. Acceptable Use

You agree not to reverse engineer, resell, or misuse the App. The calculation logic, content, and design are owned by Corithm Flow Matrix.

6. Accuracy & Updates

Tax tables are bundled and updated periodically. Rates and thresholds can change; we do not guarantee the App always reflects the latest legislation.

7. Limitation of Liability

TO THE MAXIMUM EXTENT PERMITTED BY LAW, CORITHM FLOW MATRIX SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, OR ANY FINANCIAL LOSS, ARISING FROM USE OF THE APP.

8. Changes to Terms

We may update these terms. Continued use after changes constitutes acceptance.

9. Contact

dev@corithmflowmatrix.com