25/06/2026
😄Fixed rates are reducing but why?😄
Many people think mortgage lenders simply decide what interest rates to charge, but there’s actually a key factor behind most fixed-rate mortgages: SONIA swap rates.
SONIA (Sterling Overnight Index Average) is a benchmark interest rate used throughout UK financial markets. When lenders offer fixed-rate mortgages, they often use swap markets to help secure the cost of lending money for a set period, such as 2, 3, 5 or 10 years.
Think of it like this:
🔹 Lenders don’t simply take your savings account money and lend it out at a fixed rate.
🔹 To provide certainty on a fixed-rate mortgage, they typically access the swap market to effectively “lock in” their own funding costs for that period.
🔹 They then add their operating costs, risk allowance and profit margin before offering the mortgage product to customers.
So what happens when swap rates fall?
📉 Lower swap rates = lower funding costs for lenders.
📉 Lower funding costs can allow lenders to reduce their fixed mortgage rates.
📉 Stable and gradually reducing swap rates often create a competitive environment where lenders can offer cheaper fixed-rate deals.
This is why you may sometimes see mortgage rates fall even when the Bank of England Base Rate hasn’t changed. Markets are constantly pricing in expectations for future interest rates, and swap rates often move before official rate decisions are made.
The key takeaway:
✅ Falling swap rates are generally good news for borrowers looking at fixed-rate mortgages.
✅ Stable swap rates give lenders confidence when pricing new products.
✅ Mortgage rates are influenced by market expectations, not just the Bank of England Base Rate.
If you’ve noticed fixed rates changing recently, chances are the swap market has played a significant role behind the scenes.
YOUR HOME MAY BE REPOSSESSED IF YOU DO NOT KEEP UP REPAYMENTS ON YOUR MORTGAGE.
NxtGen Mortgages is a trading name of Just Mortgages Direct limited, which is an appointed representative of The Openwork Partnership, a trading style of Openwork Limited which is authorised and regulated by the Financial Conduct Authority.
Approved by The Openwork Partnership on 24/06/2026