Remortgage Calculator
What is Remortgage Calculator?
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Imagine finding out you've been paying a "loyalty tax" on your home. That is essentially what happens when your initial fixed-rate mortgage deal ends and you automatically roll over onto your lender's Standard Variable Rate (SVR). SVRs are notoriously expensive. Remortgaging is simply the process of switching your existing mortgage to a new deal, either with your current lender or a brand-new one, to grab a much better interest rate. Think of it like switching your mobile phone provider when your contract is up to get a cheaper monthly plan, but with way bigger savings. This calculator is your financial scouting assistant. It helps you crunch the numbers to see if making the switch actually makes sense. Why do you need it? Because switching mortgages isn't always free. Lenders often charge setup fees, and your old lender might hit you with an early exit fee. Our calculator does the heavy lifting by comparing your current payments against a potential new deal, factoring in those pesky fees, and telling you exactly how many months it will take to break even and start pocketing real savings. In your daily life, using this tool means no more guessing games at the kitchen table. Whether you've noticed your home's value has gone up (which lowers your Loan-to-Value ratio and unlocks better rates) or you are coming to the end of a fixed term, this calculator gives you the hard data you need to talk to brokers with confidence. It's all about taking control of your biggest monthly bill and keeping more of your hard-earned cash in your own pocket.
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Formula
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To find your new monthly payment, we use standard amortization math:
New Monthly Payment = Remaining balance × Monthly rate / (1 − (1 + Monthly rate)^−Remaining months)
From there, we calculate your real-world savings and the path to profitability:
Step 1: Monthly saving = Old payment − New payment
Step 2: Breakeven (Months) = Total fees / Monthly savingVariable Legend
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| Symbol | Name | Unit | Description |
|---|---|---|---|
| Balance | Remaining mortgage balance | Currency | The total amount of money you still owe on your current home loan. This is the starting amount you will be refinancing with your new lender. |
| Rate | New mortgage interest rate | Annual percentage | The yearly interest rate offered by the new mortgage deal. Even a tiny drop here can translate to thousands saved over time. |
| Term | New loan term | Years | The number of years you want the new mortgage to run. Keeping it the same as your remaining years helps you compare savings fairly. |
How to Remortgage Calculator
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- 1Find your current numbers. Grab your latest mortgage statement to see your remaining balance, current monthly payment, and if you have any early exit fees.
- 2Input the new deal details. Plug in the new interest rate, the term length (years left), and any upfront fees for the new mortgage.
- 3Calculate the monthly difference. The calculator subtracts your projected new payment from your current one to find your monthly savings.
- 4Determine the breakeven point. It divides the total setup fees by your monthly savings to show you exactly how many months it takes for the switch to pay for itself.
- 5Check the Loan-to-Value (LTV) boost. If your property value has increased, your LTV drops, which automatically qualifies you for even lower interest rate tiers.
Worked Examples
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Let's say you owe £180,000 and have 20 years left. Switching from a high SVR of 6.5% to a competitive 4.5% drops your monthly payment from £1,342.01 to £1,138.71. That is an extra £203.30 back in your wallet every month! If the new mortgage has £1,500 in setup fees, you'll cover that cost in just about 7.4 months. After that, the savings are pure profit.
With a larger £250,000 balance over 25 years, moving from 5.8% to 4.2% reduces your payment from £1,581.12 to £1,346.00. Saving £235.12 per month means you will recover a £1,000 product fee in less than five months, making this a highly beneficial move.
For a smaller balance of £120,000 over 15 years, dropping your rate by 1% (from 6.0% to 5.0%) lowers your payment from £1,012.63 to £948.97. Saving £63.66 each month means it takes 18.8 months to break even on a £1,200 fee. This is still a great deal if you plan to stay in the home for a few years!
On a larger £350,000 home loan with 30 years remaining, dropping from 5.5% to 4.0% cuts your payment from £1,987.26 to £1,670.95. That's a massive monthly saving of £316.31. Even with a higher product fee of £2,000, you'll break even in just 6.3 months, saving you thousands of pounds over the years.
Real-World Applications
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Escaping the SVR Trap: Automatically moving off your lender's expensive standard variable rate when your fixed term ends to save hundreds on your monthly grocery and utility budgets.
Unlocking Home Equity: Refinancing to free up cash for major home improvements, like updating your kitchen or adding a cozy backyard deck.
Paying Off Your Home Faster: Switching to a shorter loan term with a lower interest rate to become completely debt-free years ahead of schedule.
Budget Stability: Trading a volatile variable-rate mortgage for a steady, predictable fixed-rate deal so you always know exactly what your housing costs will be.
Special Cases
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When Your Remaining Mortgage Balance is Very Small
If you only owe a small amount on your home—say, under £25,000—remortgaging might not make financial sense. Many lenders have minimum loan limits, and the flat upfront fees (like arrangement and legal fees) can easily wipe out any monthly savings you get from a lower interest rate. In this case, staying on your current rate or looking at a standard personal loan might actually be cheaper.
Having a Very Short Time Left on Your Mortgage
If you only have a few years left on your home loan, a lower interest rate won't save you as much money as it would on a fresh 30-year term. Because you are mostly paying off the principal balance rather than interest at the end of a mortgage, the cost of switching deals could easily outweigh the tiny interest savings. Always run the math to ensure you'll break even before your final mortgage payment is due.
Negative Equity and Falling Home Values
If property prices in your area have dropped and your home is now worth less than your outstanding mortgage, you are in negative equity. In this situation, switching to a new lender is extremely difficult because they cannot secure the loan against the home's value. Your best bet is usually to stick with your current lender and look into a product transfer, which typically doesn't require a new valuation.
Remortgage Steps
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| Step | Action |
|---|---|
| 1 | Dig up your current mortgage statement to find your balance and rate |
| 2 | Check for any Early Repayment Charges (ERCs) from your current lender |
| 3 | Estimate your home's current market value to find your new LTV ratio |
| 4 | Shop around and input new rates and setup fees into our calculator |
| 5 | Lock in your new deal 3 to 6 months before your current fixed term ends |
Frequently Asked Questions
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When is the best time to look for a remortgage deal?
Start shopping around roughly 3 to 6 months before your current deal expires. This gives you plenty of time to get your paperwork in order, compare rates, and complete the legal process without feeling rushed. If you wait until your deal actually ends, you'll temporarily fall onto your lender's expensive Standard Variable Rate, costing you extra money.
What is an Early Repayment Charge (ERC) and how does it affect me?
An ERC is a penalty fee charged by your current lender if you leave your mortgage deal before its official end date. These fees are usually calculated as a percentage of your outstanding loan (typically 1% to 5%), which can amount to thousands. Our calculator helps you compare these charges against your potential savings to see if it is worth waiting or switching immediately.
How does Loan-to-Value (LTV) affect the interest rates I can get?
LTV is the percentage of your home's value that you are borrowing. For example, if your home is worth £200,000 and your mortgage is £150,000, your LTV is 75%. Lenders offer significantly better rates at lower LTV tiers (like 60% or 75%) because there is less risk of them losing money if property prices drop.
Can I remortgage if I am self-employed or have a variable income?
Yes, you absolutely can, though you will need to provide more proof of income than a regular employee. Lenders typically want to see 2 to 3 years of tax returns or certified accounts to calculate your average earnings. A mortgage broker can be incredibly helpful here, as they know which lenders are most friendly to freelancers and business owners.
How does my credit score affect my remortgaging options?
Just like when you bought your home, lenders will run a credit check to ensure you are a reliable borrower. A higher credit score unlocks the absolute cheapest rates on the market, while a lower score might mean you are offered higher rates or turned down. It is always a smart idea to check your credit report and pay down any small debts before you start applying.
Common Mistakes to Avoid
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- !Forgetting to add the cost of Early Repayment Charges (ERCs) from your old lender, which can easily run into thousands of pounds.
- !Only looking at the interest rate and ignoring high product fees that make the 'cheap' deal more expensive overall.
- !Extending your mortgage term back out to 25 or 30 years just to get a lower monthly payment, which ends up costing you far more in total interest over the long run.
- !Waiting until your current deal has already ended to start looking, forcing you onto your lender's expensive standard variable rate for a month or two.
Pro Tip
Before you commit to a new deal, ask your current lender what 'product transfer' deals they can offer you. Sometimes they will match competitor rates to keep your business, and you'll save a fortune on legal fees and valuation costs because there is no new underwriting involved!
Did you know?
Did you know the word 'mortgage' comes from an Old French term meaning 'death pledge'? It sounds spooky, but it just means the deal only dies when the debt is fully paid off or the property is taken. A remortgage is simply your way of putting that pledge on a much friendlier diet!
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