Scenario 1: You Are Locked Into a Low Fixed Rate
Perhaps the most common scenario where a secured loan wins is the case of a borrower who fixed their mortgage at a low rate before interest rates rose and still has several years remaining on that fix. Millions of UK homeowners fixed at rates of 1.5% to 2.5% between 2020 and 2022, when the Bank of England base rate was at a historic low. Those homeowners are currently paying considerably less on their existing mortgage balance than the prevailing market rate.
Remortgaging to raise additional funds would mean refinancing the entire outstanding balance — say, £200,000 — at today's rates, which are significantly higher than the fixed rate they are on. The monthly payment on the existing debt would increase substantially, not just the cost of the new borrowing. A secured loan, by contrast, leaves the existing mortgage entirely unchanged. The homeowner continues paying 1.9% (or wherever they are fixed) on the existing balance and takes a second charge loan for the additional funds needed, paying today's rate only on the new money.
The arithmetic strongly favours the secured loan in this scenario unless the homeowner is approaching the end of their fixed period (within six months or so), at which point the residual benefit of the existing rate is small and remortgaging at the end of the fix — including the additional borrowing — is probably the right approach. The further into the fixed period, the more the secured loan option saves by preserving the low rate on the bulk of the borrowing.
Scenario 2: Your Early Repayment Charge Is High
Fixed-rate mortgages carry early repayment charges (ERCs) — penalties for exiting the fixed period early, typically expressed as a percentage of the outstanding balance. ERCs commonly run at 1% to 5% of the mortgage balance during the fixed period, tapering down as the fix progresses. On a large mortgage, the ERC can represent a significant sum: a 2% ERC on a £300,000 mortgage is £6,000.
Paying an ERC to remortgage makes no financial sense unless the rate saving on the new deal is large enough to recoup the charge in a reasonable timeframe (typically 12 to 24 months). In most cases, with rate differentials of one to two percentage points between the existing fix and a new deal, it takes several years to recoup a meaningful ERC — by which time the fixed period would likely have ended anyway and the homeowner could have remortgaged without penalty.
A secured loan entirely avoids triggering the ERC. Because you are not repaying or refinancing the first mortgage, the early repayment charge provision is simply not triggered. You pay the ERC of zero by leaving the first mortgage in place. This alone can justify the slightly higher rate on the second charge compared with what a remortgage rate might offer — saving £4,000 to £8,000 in ERC penalties is a significant financial benefit that makes the secured loan the better total-cost option even if its rate is higher in isolation.
Always confirm with your existing mortgage lender whether a further advance or a second charge would trigger the ERC on your existing deal. In almost all cases, neither does — but it is worth checking in writing before proceeding, particularly for non-standard mortgage products.