Mortgage & remortgage calculators

Updated 15 September 2026UK · illustrative onlyNot a lender or brokerAbout Disclaimer

Tools organised by decision stage — not a dump of widgets. Every calculator shows assumptions, validation and an illustrative-only disclaimer. Results update as you change the example inputs.

Should I switch?

Remortgage true cost calculator (fees + ERCs)
Estimate the net cost of remortgaging: early repayment charges, fees, cashback and interest difference over a comparison period.

Stay or switch?

Remortgage vs product transfer calculator
Side-by-side net cost of staying with a product transfer versus remortgaging to a new lender.

Know your payment

Mortgage repayment calculator (UK)
Standard capital-and-interest monthly payment, total interest and repayable amount with clear assumptions.

Pay down faster

Mortgage overpayment calculator
See how regular or one-off overpayments cut interest and term — with an ERC allowance warning.

Borrowing ballpark

How much can I borrow? (UK affordability)
Transparent income-multiple ballpark plus a stress-rate payment note. Not a lender decision.

Leaving a deal early

Early repayment charge (ERC) estimator
Estimate ERC using % of balance or months-of-interest methods — always check your offer wording.

Buying costs

Stamp duty calculator (England SDLT)
England & NI residential SDLT with standard, first-time buyer and additional-property rates. Wales/Scotland out of scope.

Pricing bands

LTV & equity calculator
Current LTV, equity, and how much you need to reach a target LTV band for remortgage pricing.

Mortgage & remortgage calculators

Should I switch?

Remortgage true cost calculator (fees + ERCs)

Stay or switch?

Remortgage vs product transfer calculator

Know your payment

Mortgage repayment calculator (UK)

Pay down faster

Mortgage overpayment calculator

Borrowing ballpark

How much can I borrow? (UK affordability)

Leaving a deal early

Early repayment charge (ERC) estimator

Buying costs

Stamp duty calculator (England SDLT)

Pricing bands

LTV & equity calculator