Privacy Policy for UK Mortgage & Stamp Duty

Last Updated: 11 July 2026

Not a government service. UK Mortgage & Stamp Duty is an independent third-party tool. It is NOT affiliated with, endorsed by, or operated by HMRC, GOV.UK, Revenue Scotland, the Welsh Revenue Authority, or any government department. All stamp-duty figures are estimates based on publicly available rates. Official sources include GOV.UK Stamp Duty Land Tax, Revenue Scotland LBTT and GOV.WALES Land Transaction Tax.

Overview

UK Mortgage & Stamp Duty ("the App") helps you estimate mortgage repayments, stamp duty, buying costs, affordability and rent-vs-buy for a UK home purchase. We are committed to protecting your privacy. This policy explains how information is handled.

Data Stored On Your Device Only

The App stores the following locally on your device in a private database. None of it is uploaded to us or any server:

Calculator inputs you enter (property price, mortgage amount, rate, term, deposit, income, region)
Saved scenarios you choose to keep (mortgage, stamp duty, buying costs, affordability, rent vs buy)
App preferences (theme, Material You colour setting) and premium purchase status

No account is required — no name, email, or sign-in.

Google AdMob (Free Tier Only)

Free users see ads served by Google AdMob, which may collect a device advertising ID and general usage data for ad delivery. Upgrading to Pro removes all ads. See Google's Privacy Policy.

Google Play Integrity

The App uses the Google Play Integrity API to help protect against fraud and tampering. This processes a device/app integrity signal through Google; it does not collect personal information.

In-App Purchases

The optional Pro upgrade is processed by Google Play. We receive only confirmation that a purchase completed. We do NOT receive your card details, billing address, or Google account information.

Backups You Create

The backup/export feature writes a file you choose to share or save (your saved scenarios, or a PDF summary). That file is controlled entirely by you and is never sent to us.

Data Sharing

We do NOT sell, trade, or share your personal data. The only third parties involved are Google (AdMob, Play Billing, Play Integrity) as described above, or where required by law.

Children

The App is intended for users aged 18 and over and is not directed at children.

Data Retention & Deletion

All data is stored on your device. Uninstalling the App or clearing its storage deletes everything. See our data deletion page.

Contact Us

Questions or requests: dev@corithmflowmatrix.com

Summary: Your property and mortgage inputs and saved scenarios stay on your device. No account, no personal data collected by us. Ads only for free users. Estimates only — not a government service or financial advice.