Remortgage And Overpayment Calculator
See how a different rate or extra payments change the modelled interest and term — not a lender quote.
This mortgage calculator provides estimates and does not replace professional mortgage advice.
Mortgage details
Enter the current loan and the alternative you want to model
£250,000
£250,000
Loan-to-Value (LTV)
100.0%
Required Deposit
£0
Based on a property value of £250,000 and mortgage of £250,000
4.5%
25 years
£150/month extra payment
Remortgage Options
Learn MoreRemortgage #1
(Year 5 of mortgage)
Suggested rate: 4.0%
Remortgaging Options
Use existing equity and remortgaging to fund staircasing
What This Calculator Models
Enter a property value, deposit or loan, rate and term. The illustration shows a repayment mortgage’s monthly payment, total interest and remaining balance over time. You can add a monthly overpayment and one or more remortgage dates with a new rate, a new term and an early repayment charge.
Shared ownership is available as a split: mortgage on the share you own and rent on the rest. That standalone split is for this tool. A full Kumberi journey still treats a home as fully owned on the connected timeline.
Figures use the rate and fees you type in. They are not taken from a live lender panel and they are not an affordability assessment.
Worked Example (Illustrative)
Take a £250,000 repayment loan at 4.5% over 25 years. The contractual monthly payment is the amount that would clear that loan if the rate never changed. Adding £150 a month extra reduces the balance faster, so less interest accrues in later years and the modelled term shortens.
If you remortgage in year 5 to 3.2% over 20 years and pay a £1,000 early repayment charge, the illustration nets that charge against the interest difference. A lower rate does not automatically mean a better outcome once fees and a shorter remaining term are included — the numbers on the page are there so you can see that trade-off.
What This Page Does Not Do
- It is not a mortgage offer, a Decision in Principle, or regulated mortgage advice.
- It does not check your income, credit file, or a lender’s product rules.
- Early repayment charges and overpayment allowances vary by deal; enter the figures from your offer rather than assuming 10%.
- Stamp duty, moving costs and the rest of household cash flow belong in a full journey, not only in this tool.
Related Guides
Common Questions
Is this a mortgage offer or advice from a lender?
No. Figures are educational illustrations of rate, term, overpayments and optional remortgage dates. They are not a quote, an affordability decision or regulated mortgage advice.
What can I model on this page?
A repayment mortgage or a shared-ownership split, monthly overpayments, and one or more remortgage events with a new rate, term and early repayment charge. Results show modelled interest and term change under those inputs.
How do I see this mortgage in a full journey?
After a calculation you can open a journey so housing costs sit beside tax, pensions and other life events. The standalone tool does not replace that connected timeline.