Speed and loan size usually dominate conversations about bridging finance. Yet the way interest is charged can change the final bill as much as the headline rate. Because bridging loans are short and often repaid in a single lump sum when a property sells or longer-term finance is arranged, the choice between a fixed and a variable rate deserves careful thought.
How a fixed rate works
With a fixed rate, the interest is set when the loan is agreed and does not change for the term, whatever happens to the Bank of England base rate. The main attraction is certainty: you can calculate total interest in advance and build it into a development budget or a property chain timeline. If rates in the wider economy rise during the loan, your cost stays where it was.
The trade-off is that fixed products may be priced slightly higher at the outset, and you will not benefit if market rates fall.
How a variable rate works
A variable rate is linked to a benchmark, commonly the base rate or the lender's own reference rate, plus a margin. When the benchmark moves, your interest moves with it. Variable deals can start cheaper, which appeals to borrowers who expect rates to hold steady or fall. The risk is that an increase during the term pushes up the cost, squeezing the margin on a refurbishment project or adding pressure to household finances.
Comparing the two
| Point | Fixed | Variable |
|---|---|---|
| Cost certainty | High | Lower; moves with the benchmark |
| Starting price | Can be higher | Can be lower |
| If rates rise | Unaffected | Cost increases |
| If rates fall | No benefit | Cost decreases |
| Often suits | Tight budgets, firm exit dates | Short terms, flexible budgets |
Run the numbers before you decide
Interest on bridging loans can be paid monthly, rolled up to the end or retained from the advance, and each method changes the total. Arrangement, valuation, legal and exit fees add up as well. A calculator designed for a bridge loan in the UK makes it easy to test different rates, terms and interest methods, so you can see how each option affects the overall cost before speaking to a lender.
Plan a few scenarios as well: what happens if the sale takes several months longer than expected, or if a variable rate climbs during the term? Bridging loans are usually secured on property, so failing to repay on time can lead to extra charges and, ultimately, the loss of that property. Have a realistic exit route, read the terms carefully and speak to a regulated broker or independent financial adviser, especially if the loan is secured on your home.
