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What is the SVR actually costing you?
When a fixed deal ends and nothing replaces it, the mortgage rolls onto the lender's Standard Variable Rate— and the meter starts. Nobody sends a bill for the difference; it just quietly leaves in each month's payment. This puts a number on it: your balance, your lender's SVR, and the rate you could take instead.
The SVR meter runs from the day a deal ends — not from the day the lender's letter arrives. Every month on it with these numbers is £325 of interest that a locked deal would not have charged.
Why people sit on the SVR longer than they mean to
Almost nobody chooses the SVR. It happens because the end-of-deal letter arrived in a busy month, because remortgaging feels like a project, or because "next month" repeated itself. The drift is invisible precisely because the payment simply changes and life carries on. Seeing the cumulative line above is usually the moment it stops.
The repair is mostly administrative: your own lender will usually move you to a current deal (a product transfer) with little paperwork, and a whole-market remortgage takes longer but may be cheaper. What matters is the date you start. Put your dates in and WatchMyMortgage shows the full timeline free — or for £7.99, once, watches them and emails you before the meter starts at all.
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Frequently asked questions
What is a Standard Variable Rate (SVR)?
The rate your mortgage moves to when a fixed or tracker deal ends and nothing replaces it. Each lender sets its own SVR; they are typically 2 to 3 percentage points above the fixed rates the same lender offers, and the lender can change the SVR at any time.
How much more expensive is the SVR than a fixed rate?
As of August 2026 (Bank of England data, checked 15 August 2026), the average UK SVR is about 6.6% while average new fixed rates are roughly 4.5% to 5%. On a £200,000 balance, a two-point gap is roughly £330 a month of extra interest — the calculator on this page works out your own figure.
Do I have to stay on the SVR until I remortgage?
No. Most lenders will let you switch to one of their own new deals (a product transfer) quickly, often without a new affordability check, and many let you arrange a new deal before your current one even ends. The SVR is a default, not a requirement.
Does my lender have to tell me before my deal ends?
Lenders write to you as the end date approaches, but the letter can arrive close to the date and it is easy to miss. The SVR applies from the day after your deal ends regardless of when you notice.
Figures are estimates based on the numbers you enter, using standard level-payment amortisation; SVRs change and your lender's current figure is the one that counts. This is information, not financial advice; for advice on your circumstances, speak to a mortgage adviser regulated by the FCA.