Repayment and borrowing summary
Validation and affordability warnings
Mortgage comparison
| Measure | Current mortgage | Comparison offer | Difference |
|---|---|---|---|
| Mortgage amount | £0.00 | £0.00 | £0.00 |
| Regular payment | £0.00 | £0.00 | £0.00 |
| Total interest | £0.00 | £0.00 | £0.00 |
| Total cost including fees | £0.00 | £0.00 | £0.00 |
| Approximate APR | 0% | 0% | 0% |
| Break-even point | — | ||
Mortgage balance chart
Principal and interest chart
Annual repayment chart
Cumulative interest chart
Loan-to-value progress chart
Mortgage offer comparison chart
Detailed amortisation schedule
| Payment | Date | Opening balance | Scheduled payment | Principal | Interest | Extra payment | Fees | Closing balance | Cumulative interest | Cumulative principal |
|---|
Formula used
M = P × [r(1 + r)^n] ÷ [(1 + r)^n − 1]M is the regular repayment. P is the mortgage principal. r is the periodic interest rate.
n is the payment count. Variable rates recalculate remaining payments. Overpayments reduce principal before later interest accrues.
Interest-only payments cover interest while principal remains due. Offset savings reduce the interest-bearing balance. Results remain estimates, not lending offers.
How to use this calculator
- Enter the property price and your planned deposit.
- Choose the mortgage term, rate structure, and payment frequency.
- Add lender fees, property costs, and any cashback.
- Enter overpayments, offset savings, or payment holidays.
- Provide income and spending details for affordability estimates.
- Add a comparison offer, then calculate and review results.
- Export the schedule using CSV, PDF, print, or copy.
Worked example
| Property price | Deposit | Mortgage | Rate | Term | Frequency |
|---|---|---|---|---|---|
| £300,000 | £60,000 | £240,000 | 4.50% | 25 years | Monthly |
Frequently asked questions
How are mortgage repayments calculated?
Repayment mortgages use principal, periodic interest, and payment count. Each payment covers interest and reduces the outstanding balance.
What is a mortgage deposit?
A deposit is the cash paid toward the property. The lender finances the remaining eligible purchase price.
What does loan-to-value mean?
Loan-to-value compares the mortgage balance with property value. A lower percentage usually indicates more borrower equity.
How does the interest rate affect repayments?
Higher rates normally increase repayments and total interest. Rate changes can materially affect long mortgage terms.
Is a shorter mortgage term better?
Shorter terms usually reduce total interest but increase repayments. Affordability and financial resilience remain important.
What is an interest-only mortgage?
Regular payments generally cover interest only. The original principal normally remains payable at the term's end.
How much interest can overpayments save?
Savings depend on timing, amount, rate, and lender rules. Earlier principal reductions often create larger savings.
Can mortgage fees be added to the loan?
Some lenders permit selected fees to be financed. Financed fees increase principal and usually generate additional interest.
What is fixed versus variable interest?
Fixed rates remain stable for an agreed period. Variable rates may change with lender pricing or market conditions.
How accurate is this mortgage calculator?
It provides estimates from entered assumptions. Lender methods, timing rules, taxes, and eligibility assessments can differ.
Does the result include taxes and insurance?
Entered fees and ongoing costs appear in affordability summaries. They may not form part of the lender's mortgage payment.