Mortgage payment calculator

Mobile-first, UK-focused. Offset mortgages + optional shared ownership rent. No cookies.

Inputs
Offset mortgage (how we model it)

We reduce the balance used for interest: effective principal = max(0, remaining − offset). Payment amount stays the same for a standard repayment mortgage (offset changes the interest/principal split). Show details ↓

Shared ownership
If enabled, mortgage is calculated on the owned share; rent is added for the unowned share.

Tip: for shareable scenarios, this page can encode inputs into the URL (no cookies). That’s optional and visible in your address bar.

Results
Mortgage payment (per frequency)
Interest this period (after offset)
Estimated payoff time (offset)
Shared ownership rent (monthly)
Total outpay (mortgage + rent)
Show schedule ↓

Disclaimer (2026): Estimates only; not financial guidance.