Overpaying above the allowance
If the extra payment is higher than the unused allowance, the lender may charge only on the amount above the allowance. Use the calculator to isolate that chargeable amount.
ERC Calculator
Early repayment charge calculator for mortgage switches and overpayments
Estimate the early repayment charge on a mortgage when you are overpaying above the allowance, leaving a fixed deal early or checking whether a switch could recover its upfront cost.
ERC estimateAllowance checkSwitching payback
Input Source
Use your mortgage offer, product terms or redemption statement
Allowance
Enter the allowance from your own deal rather than assuming a universal rule
Boundary
The result is an estimate, not a lender redemption figure
On This Page
Calculator
Estimate the chargeable amount before you switch or overpay
Enter the current balance, the repayment amount, the unused allowance, the ERC rate and any separate exit fee. The calculator keeps the percentage charge and administration fee separate so the total is easier to check against lender paperwork.
ERC Inputs
Enter the figures from the current mortgage offer, product switch page or redemption statement. The result is only as specific as the ERC rate and allowance you enter.
£
£
For a full switch, this is usually the balance being redeemed.
%
Many products have an allowance, but the exact rule is product-specific.
£
%
£
Keep admin fees separate from the percentage ERC if your lender lists both.
£
Optional. Use it to judge how long a switch might take to recover the charge.
Early Repayment Charge Estimate
Annual Allowance
£25,000Remaining Allowance
£25,000Amount Tested
£250,000Chargeable Amount
£225,000ERC Estimate
£6,750Exit Or Admin Fee
£100Total Charge Estimate
£6,850Charge As Share Of Repayment
2.74%Switching Payback Check
Monthly Saving Entered
£250.00Breakeven Timing
2 years 4 monthsThis only compares the charge with the monthly saving you entered.
Check the lender wording before acting
Some products apply the allowance to the balance at a specific date, some reset by calendar year, and some treat full redemption differently from partial overpayments. Match the inputs to the lender's own wording before relying on the estimate.
Common Cases
When an ERC can change the decision
The same charge can matter in different ways depending on whether you are overpaying, redeeming the mortgage or switching product early.
Leaving a deal before it ends
A lower replacement rate can still lose once the ERC, new product fee and switching costs are included. Compare the full upfront cost before treating the rate gap as a saving.
Closing or transferring the account
Some statements show a separate exit or closure fee as well as any ERC. Keep that line separate so you do not confuse an administration fee with the product charge.
Lender Terms
The lender wording matters more than a generic rule
ERC rules can depend on the product, the anniversary date, the current balance, whether the repayment is partial or full, and whether the deal is ending soon.
Match the allowance period
Some allowances reset by calendar year, some by mortgage year and some use a balance measured on a particular date. Use the period shown in your own terms.
Check whether the rate steps down
Some fixed deals use a charge that changes as the deal gets closer to expiry. Enter the rate that applies on the date you expect to repay or switch.
Ask for a redemption figure before acting
For a real sale, full repayment or switch, the lender redemption figure is the figure to rely on. Use this calculator to prepare the comparison before requesting or reviewing that figure.
Next Tools
Use the ERC result with the wider mortgage decision
Once the charge is visible, the next question is whether the switch, overpayment or waiting option still makes sense.
Remortgage Calculator
Compare leaving early with waiting until the current deal ends.
Overpayment Calculator
Compare extra payments with keeping cash available before committing the money.
Fees Calculator
Add product fees, legal work and other costs around the ERC estimate.
Early Repayment Charge Guide
Read the guide if you need to separate ERCs, exit fees, allowance rules and lender redemption figures before acting.
Frequently Asked Questions
What is an early repayment charge?
An early repayment charge is a fee a lender may apply if you repay, switch or overpay beyond the allowance while the mortgage product is still inside a charge period.
Can this calculator tell me the exact charge?
It can estimate the charge from the balance, allowance, ERC rate and exit fee you enter. The exact charge still depends on the lender wording in your offer, product terms or redemption statement.
Is an exit fee the same as an ERC?
No. An ERC is usually linked to leaving a mortgage product early or overpaying beyond the permitted allowance. An exit or account closure fee is normally an administration charge for closing or transferring the mortgage account.
Should I pay an ERC to switch mortgage deals?
Only compare that after the full switch cost is visible. The replacement rate, new product fee, legal or valuation costs, remaining months on the current deal and the ERC all affect the answer.