One of the most common calls I get is from homeowners who need extra money and aren’t sure whether to go back to their existing lender or look elsewhere. The answer depends entirely on their individual situation — but additional mortgage borrowing is often a route worth exploring before jumping straight into a full remortgage.
Additional mortgage borrowing means asking your current lender to advance you more money on top of your existing loan. It’s sometimes called a further advance. The extra amount is usually secured against your property, the rate may differ from your original deal, and you’ll repay it alongside your existing mortgage. It won’t always be the cheapest option — but it can be simpler and faster than switching lenders entirely.
Important Information
Your home may be repossessed if you do not keep up repayments on your mortgage.
Additional borrowing on your mortgage is secured against your property. This means you could be putting your home at risk if repayments are not maintained.
If you are using additional borrowing for debt consolidation, you may pay more interest overall, even if your monthly payments are lower. You will also be converting unsecured debt into secured debt against your home.
Early repayment charges may apply if you change your existing mortgage or repay it early as part of a remortgage or refinancing.
All lending is subject to status, affordability, and lender criteria. The amount you can borrow and the rate offered will depend on your individual circumstances.
Interest rates can change over time. Lenders will assess whether you can afford repayments not only at current rates but also if rates were to increase, in line with guidance from the Financial Conduct Authority and the Bank of England.
Further advances, remortgages, and second charge mortgages are all secured lending. Each option carries different costs, risks, and suitability depending on your situation.
What Is Additional Mortgage Borrowing?
Put simply, it’s borrowing more money from your existing mortgage lender without remortgaging. Your lender advances you a further sum — usually at a separate rate — and this sits alongside your current mortgage. Because it’s secured against your property, the rate is typically lower than a personal loan or credit card. That said, your home is at risk if you don’t keep up repayments, so it’s not a decision to take lightly.
The difference between additional mortgage borrowing and remortgaging is worth understanding. With a remortgage, you either switch to a new deal with your existing lender or move to a new lender entirely, often borrowing more in the process. Additional borrowing keeps you with the same lender on your current deal, with the extra amount running separately. Which route works better depends on your rate, how much equity you have, and whether your lender will accommodate you.
What Can I Use Additional Mortgage Borrowing For?
Most lenders will consider additional borrowing for home improvements, debt consolidation, and other significant personal expenditure. Home improvements are usually the most straightforward purpose to approve — lenders like to see money going back into the property. Debt consolidation is possible, but lenders will look carefully at whether it’s genuinely affordable and suitable. Moving short-term debt onto a long-term secured loan isn’t always the right answer, even if the monthly payment looks lower.
Other common reasons include funding school or university fees, covering a large one-off expense, or helping a family member. Some clients use it to raise a deposit for a buy-to-let property. Lenders may have views on what purposes they’ll accept, so it’s always worth checking before you assume.
How Much Can I Borrow?
There’s no single answer — it depends on your lender, how much equity you have, your income, and your overall financial commitments. Most lenders won’t advance further funds beyond 80% to 85% of your property’s current value, though some may go higher or lower. For interest-only mortgages, the maximum loan-to-value is often lower — typically around 75%. You can get a rough sense of the numbers using our mortgage calculator.
Most lenders also apply a minimum borrowing amount — often around £10,000, though this varies. If you need less than that, other forms of borrowing may be more appropriate. Affordability is assessed in full, just as it was for your original mortgage. Your income, outgoings, and existing credit commitments will all be reviewed. The FCA’s mortgage rules require lenders to stress test affordability, meaning they’ll check you could still manage repayments if interest rates were to rise.
What Do Lenders Look At?
The criteria for additional mortgage borrowing is similar to a new mortgage application. Lenders will check your income, your outgoings, how you’ve managed your existing mortgage payments, and your credit history. A strong payment track record on your current mortgage helps considerably. Missed payments in the recent past could make approval harder — some lenders won’t offer further advances if there have been arrears within the last 12 to 24 months.
Equity is the other key factor. If house prices have risen since you bought, your loan-to-value ratio may have improved, giving you more room to borrow. If prices have fallen, or if you’ve not been paying down capital for long, there may be less available. It’s always worth checking your credit file before you apply — you can check your credit report here to make sure there are no errors or surprises before anything is submitted.
Which Lenders Offer Additional Mortgage Borrowing?
Most mainstream UK lenders offer some form of further advance, though the terms, rates, and criteria vary considerably. The lenders below are among those that commonly provide this facility — but their criteria, maximum loan-to-value, and eligible purposes change regularly, so it’s essential to check current terms directly or through a broker.
- Nationwide Building Society — offers further advances to existing mortgage customers, subject to affordability and loan-to-value limits. Terms and eligible purposes are assessed on a case-by-case basis.
- Barclays — provides further advances to eligible existing customers. Rates and maximum amounts depend on current loan-to-value and individual circumstances.
- NatWest — allows existing customers to apply for additional borrowing, including for debt consolidation purposes, subject to their current lending criteria and affordability checks.
- Halifax — offers further advances to existing customers for purposes including home improvements and debt consolidation. Conditions apply and are subject to affordability assessment.
- Santander — provides further advances to eligible customers. Santander has also offered green additional borrowing products for energy-efficient improvements, though availability is subject to change.
- HSBC UK — offers additional borrowing to existing mortgage holders, with options that may include switching to a new product at the same time. Eligibility and limits depend on individual circumstances.
- Leeds Building Society — provides further advances to existing borrowers, including fixed-rate options. Terms vary and eligibility is assessed on application.
- The Co-operative Bank — offers further advances for existing customers. As with other lenders, terms are subject to affordability assessment and current lending policy.
- Yorkshire Building Society — provides further advances for existing borrowers, with options that may include offset arrangements. Eligibility depends on current loan-to-value and affordability.
Please note that criteria, maximum loan-to-value limits, and eligible purposes change regularly with all lenders. I’d always recommend getting proper mortgage advice before approaching your lender directly, so you understand your options in full.
Is Additional Mortgage Borrowing Better Than Remortgaging?
It depends on your situation. If you’re mid-way through a fixed-rate deal, remortgaging to a new lender could trigger early repayment charges — and those can be substantial. In that case, a further advance from your existing lender might make more sense, even if the rate isn’t quite as sharp. On the other hand, if your fixed rate is ending soon and you want to borrow more, a full remortgage might let you consolidate everything into a single deal at a better overall rate.
There’s no universal answer here. What I usually do is run through the numbers for both options and show the client the total cost of each. Sometimes the further advance wins. Sometimes the remortgage is clearly better. Occasionally a second charge loan — secured against the property but through a separate lender — works out as the most practical route, particularly if the existing mortgage rate is very low and worth keeping. It’s worth understanding all three before committing to any of them.
What Happens if I Have a Bad Credit History?
A less-than-perfect credit record doesn’t automatically rule out additional mortgage borrowing, but it can limit your options. Most high street lenders are cautious about offering further advances to borrowers who’ve had recent missed payments, defaults, or county court judgements. The more recent the issue, the harder it tends to be. If your existing lender says no, a full remortgage to a specialist bad credit mortgage lender may be worth exploring instead, though rates will typically be higher. Taking specialist mortgage advice before making any application is important here — a declined further advance can affect your credit file.
Self-Employed Applicants
If you’re self-employed, the income assessment for additional mortgage borrowing follows broadly the same rules as a standard mortgage application. Lenders will usually want to see at least two years of accounts or SA302s, though some may work with one year’s figures in the right circumstances. How they calculate your income — whether from net profit, salary plus dividends, or day rate — varies between lenders. Getting the right lender from the start avoids wasted time and unnecessary credit footprints.
A Realistic Example
A couple came to me who’d owned their home for eight years and had built up a decent amount of equity. They wanted to extend the kitchen and convert the loft — a project quoted at around £55,000. Their existing lender was willing to advance the full amount as a further advance, but the rate on offer was noticeably higher than what was available on a remortgage. Their fixed rate had six months left to run, so there would have been an early repayment charge to exit early. We looked at the numbers both ways. The early repayment charge plus remortgage costs made switching more expensive in the short term, but over the full five-year period of the new deal, remortgaging came out cheaper overall. They waited until the fixed rate expired, then remortgaged with the full additional borrowing included. A straightforward outcome — but only because they took the time to compare both options properly.
What Are the Risks?
The main risk is straightforward: this is secured borrowing. If repayments aren’t kept up, the lender could ultimately repossess your home. That sounds stark, but it’s important to say clearly. Affordability needs to be assessed honestly — not just what you can afford today, but what happens if your income changes or interest rates rise. The Bank of England base rate has moved considerably in recent years, and anyone taking on additional secured debt should factor in the possibility of further changes.
Debt consolidation deserves particular care. Moving unsecured debt — credit cards, personal loans — onto your mortgage reduces the monthly payment, but it extends the repayment period considerably. You could end up paying significantly more in total interest over time, even at a lower rate. It can still be the right decision in some circumstances, but I always make sure clients understand the full picture before recommending it. The FCA’s consumer guidance on mortgages has a clear explanation of how secured borrowing rules apply in this context.
Next Steps
If you’re considering additional mortgage borrowing, the best starting point is to get a clear picture of your options. Use our mortgage calculator to get an initial sense of the numbers. Then get in touch for proper mortgage advice — I can review whether a further advance, a remortgage, or another route makes the most sense for your specific situation. There’s no obligation, and no application goes anywhere until you’re happy with what’s on the table.
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2: We will research the whole market and email you a detailed quote as well as a list of documents to proceed.
3: You upload the documents and information needed via our channel our online portal.
FAQs – Additional Mortgage Borrowing
What is additional mortgage borrowing?
It’s when you ask your existing lender to advance you more money on top of your current mortgage. The extra amount is secured against your property and usually runs at a separate rate. It’s sometimes called a further advance. Common reasons include home improvements, debt consolidation, or funding a significant one-off expense. Because it’s secured lending, the rates are generally lower than personal loans — but your home is at risk if you don’t keep up repayments.
Will I pay fees?
Possibly. Some lenders charge a product fee or arrangement fee for a further advance, just as they might for a new mortgage. Valuation fees may also apply if the lender wants to confirm the current value of your property. It’s worth asking your lender for a full breakdown of costs before proceeding, and comparing those costs against alternative options like a personal loan or remortgage.
How much extra can I borrow?
This depends on how much equity you have, your income, and the lender’s maximum loan-to-value. Most lenders won’t advance beyond 80% to 85% of the property value in total — including your existing mortgage. There’s also usually a minimum borrowing amount, often around £10,000. Your income and outgoings are reassessed in full, and affordability must stack up on the new combined payment.
Can I borrow more if I’m on a fixed-rate mortgage?
Yes, in many cases. Your lender may offer a further advance that runs alongside your existing fixed-rate deal, at a different rate. If you’re thinking about remortgaging to release equity instead, it’s worth checking whether early repayment charges apply first. In some situations, waiting until the fixed rate ends and then remortgaging the full amount is the more cost-effective approach.
Does debt consolidation through additional borrowing make sense?
It can reduce your monthly outgoings, but it’s not always cheaper overall. Spreading short-term debt over a long mortgage term means more interest paid in total, even at a lower rate. It makes most sense when the monthly cash-flow benefit is genuinely needed and the total interest cost has been properly compared. I’d always want clients to see both sides of the numbers before making that decision.
What if my lender turns me down?
A refusal from your existing lender doesn’t necessarily mean you’re out of options. Remortgaging to a new lender — and borrowing the extra amount as part of that — is often possible where a further advance isn’t. For those with credit difficulties, specialist lenders may be able to help, though rates will typically be higher. It’s worth taking proper mortgage advice before making further applications, as unnecessary declined searches can affect your credit file.
