★ Key Takeaways
- ✓Start your remortgage search 3–4 months before your fixed deal ends — not the week it expires
- ✓Don't judge a mortgage by its interest rate alone — total cost including fees is what matters
- ✓Your existing lender's retention offer is rarely the best deal available to you on the open market
- ✓Ignoring early repayment charges can turn a good-looking switch into a costly one
- ✓A broker does the market comparison for you — and saves you from making any of these mistakes
Remortgaging is one of the most effective ways to reduce your monthly outgoings — but it's also an area where people consistently leave money on the table by moving too slowly, comparing the wrong things, or sticking with whoever they're already with out of inertia. Here are the five mistakes I see most often, and exactly how to avoid them. If you want a full overview of when and why to remortgage, our guide to remortgaging in Scotland: when, why, and how to switch covers the whole process from start to finish.
Waiting Until Your Fixed Deal Has Already Ended
When your fixed-rate deal expires, you're automatically moved onto your lender's Standard Variable Rate (SVR) — and SVRs are almost always significantly higher than the fixed rates on the open market. In recent years, SVRs have frequently sat at 7–8% while new fixed deals were available at 4–5%. Every month you spend on the SVR is money lost.
Most lenders allow you to lock in a new deal up to 6 months before your current one ends — and you don't switch until the existing deal expires. Starting your search 3–4 months out gives you time to compare properly, complete the application, and avoid any gap on the SVR.
Not Checking Your Credit File Before Applying
Even if you've had a mortgage for years, a credit issue that appeared since you last applied can affect your remortgage options. A missed payment, a new CCJ, or even an unexplained address discrepancy can cause lenders to either decline you or push you toward higher rates. The time to discover these issues is before you apply — not after a hard credit search has left a footprint.
Check all three main credit agencies (Experian, Equifax, TransUnion) two to three months before you plan to apply. That gives you time to raise disputes, get errors corrected, and give your score the chance to recover before any lender looks at it.
Comparing Interest Rates Instead of Total Cost
A mortgage with a 4.1% rate and a £999 product fee can easily cost more over a 2-year fixed term than a 4.3% rate with no fee — especially on a smaller mortgage balance. Yet most people instinctively chase the lower headline rate without running the numbers. The true comparison is: (monthly payment × term in months) + all fees = total cost.
Some products also come with cashback or free valuation/legal fees when switching — which further changes the real-world comparison. A broker will do this calculation across dozens of deals on your behalf, so you're always comparing apples with apples.
Automatically Accepting Your Current Lender's Retention Offer
When your fixed deal approaches its end date, your existing lender will typically write to you with a "product transfer" or retention offer — a new rate they'll move you onto. It's framed as helpful. It arrives in the post. It feels easy. And it is almost never the best deal available to you.
Lenders make their retention offers competitive enough to keep existing customers, but not competitive enough to attract new ones from the open market — because existing customers are statistically less likely to shop around. Use their offer as a benchmark, not a destination. A quick broker search will tell you within hours whether the market can beat it.
Overlooking Early Repayment Charges on Your Current Deal
Switching mortgage before your current fixed-rate period ends usually triggers an Early Repayment Charge (ERC). These are typically 1–5% of the outstanding mortgage balance — on a £150,000 mortgage, that could be £1,500 to £7,500. In most cases, paying an ERC to switch early doesn't make financial sense unless rates have dropped dramatically.
Always check your mortgage terms or ask your lender for the exact ERC figure before making any decisions. The exception: some lenders allow you to port your mortgage to a new property without triggering the ERC — worth checking if you're planning to move before your deal ends.
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Book a free consultationFrequently Asked Questions
How much can remortgaging save me?
It depends on how far your current rate is from the best available market rate and the size of your outstanding balance. On a £200,000 mortgage, moving from a 7% SVR to a 4.5% fixed deal saves roughly £4,800 per year in interest. Even a smaller difference of 1% on a £150,000 balance saves £1,500 a year.
Do I need a solicitor to remortgage?
If you're staying with the same lender (a product transfer), no solicitor is needed. If you're switching to a new lender, conveyancing is required — but most lenders include a free legal service as part of their remortgage deal, so in practice you often won't pay legal fees. Your broker will confirm what's included with each deal.
Can I remortgage to release equity?
Yes — if your property has gone up in value since you bought it, you may be able to remortgage for a higher amount and release some of that equity as cash. This is commonly used for home improvements, consolidating debts, or helping children with deposits. The additional borrowing will increase your monthly payments, and your new loan-to-value ratio will determine the rates available.