What does this mortgage comparison calculator show?

It compares two repayment mortgage rates using the same loan amount and term, then estimates monthly payment, total payment, and total interest.

Does it include mortgage fees?

No. It excludes arrangement fees, broker fees, valuation fees, legal costs, cashback, early repayment charges, and product-specific terms.

Can I compare a zero-interest mortgage?

Yes. A zero-interest option is treated as straight-line repayment of the loan amount over the selected term.

Does this model remortgaging?

No. It assumes each rate applies for the full mortgage term and does not model future fixed-rate periods or variable rates.

Is this mortgage advice?

No. It is a comparison model and does not consider affordability checks, lending criteria, fees, product terms, or your personal circumstances.

Property planning

Mortgage Comparison Calculator

Compare two mortgage rates against the same loan amount and term to estimate monthly payment, total payment, and total interest differences.

Use this mortgage comparison calculator to compare two fixed-rate repayment scenarios before checking full product fees, affordability, and lender terms.

Inputs

Compare two fixed-rate mortgage options against the same loan amount and term.

Loan Amount (£)

Loan Term (years)

Interest Rate 1 (%)

Interest Rate 2 (%)

Results

Review monthly payment, total payment, and interest differences.

Enter two mortgage rates and compare to see payment and interest differences.

Assumptions

What this mortgage comparison assumes

These assumptions keep the calculator focused on rate and interest differences.

Rates

Fixed rates

Each option assumes the selected interest rate applies for the full mortgage term.

Loan amount

Same balance

Both options use the same loan amount so the rate comparison stays isolated.

Term

Same mortgage term

Both options are repaid over the same number of years.

Fees

Not included

Arrangement fees, valuation fees, legal fees, and cashback are not included.

Remortgage events

Not modelled

The calculator does not model future remortgages or variable-rate changes.

Overpayments

Not included

Both options assume standard monthly repayment with no overpayments.

Examples

Common mortgage comparison scenarios

Use these examples to think through monthly affordability, total interest, and product comparison limits.

Lower rate comparison

A borrower compares two fixed rates for the same mortgage balance.

The monthly payment difference shows the immediate affordability impact.
The total interest row shows the long-term cost difference.
A small rate gap can become meaningful over a long term.

Deal length thinking

A borrower uses the total cost view before checking real product terms.

The calculator keeps the term fixed, so it is a clean rate comparison.
Actual fixed-rate deals may have different fees or early repayment charges.
Use this as a first-pass model before comparing product documents.

Affordability vs interest

A user compares the lower monthly payment with the lower total interest option.

The lowest monthly payment and lowest interest option will often be the same here.
Fees and product terms can change that conclusion in the real world.
Debt reduction and investing choices can sit alongside mortgage decisions.

FAQ