Mortgage Overpayment Calculator
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Mortgage Overpayment Calculator
Before you consider overpaying your mortgage, ask your mortgage lender if they allow it without incurring a penalty and what restrictions may apply to the amount.
If your lender has you on their standard variable rate, you can usually make an unlimited number of overpayments. However, if you have a fixed-rate mortgage or tracker mortgage, the yearly limit for total outstanding balance is capped at 10%.
Our calculator is an excellent source of rough estimates for calculating the 10%, but it’s always advisable to speak with your lender in order to make sure you get the most out of overpaying. Furthermore, while making any type of additional payments ensure that they are going towards reducing the debt instead of shortening monthly payments as this is where you’ll see true benefits. Our calculator makes these assumptions assuming that each payment towards your mortgage will reduce its amount debt-wise.
Read our guide to learn more: Can I overpay my mortgage?
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Frequently Asked Questions
How Does Mortgage Overpayment Work?
Making overpayments on your mortgage allows you to pay off your loan faster, reduce the total interest paid, and shorten your mortgage term. Overpayments can be made in two ways:
- Regular Overpayments – Increasing your monthly mortgage payments beyond the required amount.
- Lump-Sum Overpayments – Paying a larger one-off amount from savings, bonuses, or offset mortgages.
Before making an overpayment, check with your lender to ensure the extra funds are applied directly to the capital balance rather than just reducing future payments. Also, be aware that some lenders impose restrictions or fees on overpayments, so reviewing your mortgage terms is essential before proceeding.
How much overpayment can I make on my mortgage?
The amount you can overpay without penalties depends on your mortgage lender and the terms of your loan. Many lenders allow you to overpay up to 10% of the outstanding balance per year without incurring fees, but this varies. If you’re unsure about your lender’s overpayment policy, it’s best to contact them directly to confirm any restrictions, limits, or potential charges.
While overpaying can save you money on interest and help you become mortgage-free sooner, it’s important to consider other financial priorities before committing extra funds. Building an emergency fund, paying off high-interest debts, or investing in retirement savings may offer better financial benefits depending on your circumstances.
Ultimately, deciding whether to overpay your mortgage depends on your financial goals and overall situation. If you’re unsure, seeking advice from a mortgage specialist or financial adviser can help you determine the best strategy for your long-term financial health.
- Mortgage Repayment Calculator – Estimate your monthly payments based on loan amount, interest rate, and term.
- Overpayment Calculator – See how extra payments can reduce your mortgage term and interest costs.
- Affordability Calculator – Assess how much you might be able to borrow based on your income.
- Stamp Duty Calculator – Work out the tax costs on your property purchase.
- Debt-to-Income Calculator – Check if your existing financial commitments could impact your mortgage eligibility.
- Rental Yield Calculator – For landlords, calculate the return on investment for buy-to-let properties.