Free UK calculator

What is staying on your current mortgage rate costing you?

Compare your current rate with a potential replacement, then include fees and cashback to see the true-cost saving and break-even point.

Repayment mortgagesInputs stay in your browserMethod checked July 2026

Your mortgage

Use your latest statement for the balance and remaining term.

Outstanding balance£

Remaining termyears

Your current rate%

Potential new rate%

Compare overyears

New product fee£

Other switching costs£

Cashback£

Add the product fee to the new mortgage rather than paying it upfront

Enter a valid balance, term and both interest rates.

The calculation happens on this page. The numbers you enter are not sent to Money Harbour.

Your estimate will appear hereWe compare the same balance and term at both rates, using standard repayment-mortgage maths.

Estimated monthly saving

£0/mo

before fees and other costs

Current£0

New£0

Net saving in selected period

£0

True-cost break-even

—

Current payment

£0

New payment

£0

True cost includes payments, fees, cashback and the balance remaining—not just the monthly-payment difference.

Before acting: this is an illustration, not a mortgage quote. Your available rate and payment depend on lender criteria, fees, property value, credit checks and personal circumstances.

The calculation

How the maths works

We use the standard repayment-mortgage amortisation formula and compare the same outstanding balance and remaining term at both annual rates. See the full method and assumptions.

The decision

Use the true break-even point

The upgraded result compares fees, cashback, interest and the mortgage balance remaining each month. Add any early-repayment charge under other switching costs. Understand each remortgage fee.

Optional research list

Rates move. Get told when yours is beatable.

We're exploring a free rate-alert service. Leave your email if you want to hear when it launches. The calculator itself remains free and does not require signup.

Practical guides

Understand the decision, not just the number.

Should I remortgage?→Current UK SVR rates→Product transfer vs remortgage→Fees and the break-even sum→How long a remortgage takes→