Find out how much equity you can release, and what it will cost each month
A second charge, often called a second mortgage, sits behind your existing mortgage. Same property, second legal charge, and the first mortgage carries on exactly as before. The money comes from equity: what the property is worth, less what you still owe on it.
Start the calculator there. Put in the value, the balance on your first mortgage and the type of property, and it shows the most a lender is likely to allow. Pick an amount and you get the monthly payment, the interest, any fees and the combined loan to value. Paying off other debts with the loan? There is a setting for that too.
Second charge mortgage calculator
Every figure is an estimate. The starting rate matches the combined loan to value you enter, and you can type over it with a rate you have been quoted.
Second Charge Mortgage Calculator UK
See how much equity you can release, then the monthly payment and total cost.
Get a formal quote
Happy with the figures? Open the form below and your results are added to the message box for you. Add your details and anything else we should know, send it, and a specialist will come back with lender options and a formal quote.
How the second charge calculator works
Property first. Enter the value and the balance left on your first mortgage, then choose the type: owner-occupied home, buy-to-let, or commercial and semi-commercial. The type matters because lenders limit how much of the value can be secured. Homes can go to 100% combined, buy-to-let sits around 75% and commercial around 65%, and the calculator works to those limits. Whatever is left after your first mortgage is your headroom, the most you could borrow on paper.
Then the loan. Choose an amount and a term. The rate fills itself in and climbs as the loan takes a bigger share of the property. Fees can come out of your own cash or be added to the loan, and added fees collect interest for the whole term.
Clearing debts with the loan? Tick the box, enter what you owe and what you pay each month, and the calculator sets the old payments against the new one. A smaller monthly figure over a longer term usually costs more in total. You will see by how much.
Working out how much equity you can release
Lenders measure risk with combined loan to value, shortened to CLTV. Add your first mortgage to the new loan, then divide by the property value. Each lender sets its own limit. The second charge lender gets paid only after the first charge lender is cleared, so a higher CLTV means a higher rate to cover that position.
To find your headroom, multiply the property value by the lender’s limit and take off the first mortgage balance. The limit moves with the property and with what the money is for: up to 100% on an owner-occupied home, around 75% on a buy-to-let, around 65% on commercial or semi-commercial property. Pricing climbs as CLTV rises, and the top of the range on a home comes from fewer lenders. Our second charge mortgage rates page shows how rates move band by band.
A £60,000 extension on a £420,000 home
The home is worth £420,000 with £252,000 left on the mortgage. That is 60% loan to value and £168,000 of equity. A lender working to 85% allows total secured debt of £357,000, which leaves £105,000 once the first mortgage is taken off. At 100% the whole £168,000 is in reach, though lenders that go that far charge more.
The extension needs £60,000. Total debt rises to £312,000, or 74% combined. Over fifteen years at 8.5% the second charge costs about £591 a month. Interest over the full term comes to about £46,400.
A £45,000 loan at a high combined loan to value
The property is worth £300,000 with a £240,000 mortgage, so 80% loan to value. The owner wants £45,000. Total borrowing goes to £285,000, or 95% combined. Some lenders allow that on an owner-occupied home. Many stop at 85%.
At 11.75% over fifteen years the payment is about £533 a month and interest totals about £50,900, more than the £45,000 borrowed. A smaller loan is worth trying in the calculator before going further.
A £50,000 deposit raised on a rental
Investment property is capped tighter, and that one difference drives the whole result.
The property is worth £300,000 with £165,000 of buy to let borrowing against it. Equity is £135,000, but a 75% limit allows total debt of only £225,000. Only £60,000 can be reached.
The landlord takes £50,000 toward the deposit on the next purchase. Total borrowing reaches £215,000, or 72%. Investment lending is priced above owner-occupied, so this example uses 10.5%. Over ten years the payment is near £675 a month, and interest adds up to about £31,000.
£38,000 of debts cleared on a £350,000 home
The home is worth £350,000 with £180,000 left on the mortgage. The owner has £38,000 of debt spread over a personal loan, a car finance agreement and credit cards. Payments come to £1,150 a month, with around forty months to run. A £38,000 second charge takes total borrowing to £218,000, or 62% loan to value.
Over fifteen years at 8.5% the new payment is about £374 a month, a drop of about £776. The total goes the other way. Clearing the old debts on their current terms costs £46,000. The new loan costs about £67,400, roughly £21,400 more. Over ten years the payment is about £471 and the total about £56,500, which is about £10,500 above the old debts. A shorter term costs more each month and cuts the extra interest. Our page on mortgage debt consolidation covers when this works and when it only pushes the problem back.
Rates here are for illustration and are not quotes. Ceilings differ between lenders, rates move, and your own figure depends on the case you put in front of them.
What decides the amount a lender will release
Headroom on paper is where the process starts. Lenders then test it against several things:
- Affordability. Lenders add the new payment to your mortgage and every other commitment, then check the total against your income.
- Purpose. Home improvements, a tax bill, debt consolidation and business investment all get funded. Some reasons draw closer questions than others.
- Property type. Owner-occupied houses reach the highest limits. Flats, houses in multiple occupation, mixed-use and commercial property face tighter terms.
- Credit history. A poor record narrows the panel and lifts the rate, but strong equity still gives lenders something to work with. Our adverse credit mortgages page explains how they weigh it.
- Term. Stretch the loan and the monthly payment falls while the interest bill rises. The worked examples above show the scale.
- Valuation. The lender sends its own valuer, and that figure replaces yours in the calculation.
Where the calculator stops and a broker starts
A calculator tells you what a given amount costs and how much equity it uses. It cannot say which lenders will take your case, where they set their limits for your type of property, or how to present the application so underwriting goes through first time.
Commercial Finance Network covers the full second charge panel. Before you apply anywhere, we will tell you what is realistically on offer against your equity and what it will cost. Our second charge mortgage page explains the product in full, and the comparison of second charge, remortgage and further advance is useful when you are still choosing between them.
Frequently Asked Questions
How much equity can I release with a second charge?
It depends on the property type and the lender’s limit on combined loan to value.
Homes can reach 100% combined, buy-to-let around 75% and commercial around 65%. Multiply the value by the limit, take off your first mortgage, and the remainder is your headroom on paper. Affordability, credit history and the lender’s valuation then settle what is actually released.
Is the rate in the calculator the rate I will be offered?
No. It is a typical starting figure for the combined loan to value you enter.
Lenders price on CLTV, credit history, property type and what the money is for, so your own rate could land above or below it. Type in a quoted rate to test your case.
Should I add fees to the loan or pay them upfront?
Adding fees to the loan keeps your cash free today and costs more over the term.
Add £2,000 of fees to a £60,000 loan over fifteen years at 8.5% and the payment rises by about £20 a month, with about £1,500 more interest. The calculator lets you switch between paying upfront and adding them.
Does the calculator show the cost of consolidating debts?
Yes. Tick the debt consolidation box and the calculator compares the new payment and total cost with what you pay now.
A longer term usually lowers the monthly figure and raises the total interest, and debts that were unsecured become secured on your home. Seeing the monthly saving next to the extra total cost lets you judge the trade for yourself.
Is a second charge cheaper than remortgaging?
Sometimes. It depends on the rate on your current mortgage and any early repayment charge.
A second charge leaves the first mortgage alone, which helps if that mortgage carries a low fixed rate or a charge for leaving early. A remortgage replaces everything at a single rate. The answer comes from putting the blended cost of the two routes side by side, and we do that for you before anything goes to a lender.
Can I use the calculator if my credit history is poor?
Yes, although expect a rate above the starting figure.
Poor credit usually shows up in the rate and in how much a lender will release. Strong equity still gives the lender something to lean on. Type in the rate you have been quoted, or raise the starting figure, to see the effect on the payment.
Final Thoughts
A calculator can show you the numbers. Equity, income, the property and the lender decide whether you can get them, and those four are best looked at together.
Commercial Finance Network is a whole-of-market commercial finance broker working with homeowners, property investors and businesses across the UK and internationally. We are directly authorised and regulated by the Financial Conduct Authority.
Think carefully before securing other debts against your home. Your home may be repossessed if you do not keep up repayments on your mortgage. Second charge lending taken for business purposes or secured against investment property is not regulated by the Financial Conduct Authority.
Call us on +44 1494 622 111 or email info@cfnuk.com to speak to a specialist directly.
Related Pages
- Second Charge Mortgages on Buy-to-Let Property – How lenders treat investment property as security.
- Second Charge Mortgages for Commercial and Business Purposes – Raising capital against commercial property, and where the unregulated side begins.
- Second Charge Bridging Loan – Short-term secured money for deals that cannot wait.
- Second Charge Lending for SPVs, Trusts and LLPs – How trusts, LLPs and SPVs change the underwriting.
- Second Mortgage to Consolidate Unsecured Debt – Unsecured debt cleared with a second charge, shown as a worked case.
