Nothing dramatic happens on the day itself. Your mortgage does not end, nobody asks for the balance back, and the direct debit keeps going out. What changes is the interest rate: you move onto your lender's standard variable rate, and your monthly payment moves with it.
That is the default, and it is almost always the worst outcome. As of mid 2026, typical standard variable rates sit between 6% and 7%, while the best two year fixes start around 4.3% and five year fixes around 4.4%. On a £200,000 balance, a two percentage point difference is roughly £4,000 a year in interest. That is the price of not getting round to it.
So the short answer: act, and start about six months before your deal ends.
Immediately, in practice. Most lenders switch the rate on the first payment date after your deal expires, so the very next payment is the higher one. There is no grace month.
Standard variable rates also move whenever the lender decides they should. They are loosely tied to the Bank of England base rate, currently 3.75%, but no lender has to pass on a cut in full. You are on a rate someone else controls, with no ceiling and no end date.
Roughly 1.8 million fixed rate deals expire during 2026, many of them five year fixes taken at under 2% in 2021. If that is you, moving to something around 4.4% is a real increase and worth budgeting for honestly. It is also manageable if you plan for it. The people who get hurt are the ones who let the deal lapse and then spend four months on the standard variable rate while they think about it.
The most expensive mortgage decision most people make is the one they never get round to making.
Most lenders let you apply for a new deal up to six months before your current one ends, then hold that rate until your existing product expires. You are not paying the new rate early. You are reserving it.
That hold is the useful part. If rates rise before your switch date, you keep the rate you locked. If they fall, most lenders will let you rebook onto the cheaper product before completion, though the rules vary, so ask rather than assume.
The second reason is practical. Moving to a new lender means an application, a valuation and conveyancing, and four to eight weeks is common. Start three weeks out and you will probably spend time on the standard variable rate whether you like it or not. Our guide on how early you can remortgage in the UK covers the mechanics.
There are only three. Everything else is a variation on one.
A different lender repays your existing mortgage and takes over the security on your property. This opens the whole market. If your current lender is not competitive at your loan to value, or does not lend the way your income works, this is how you get away from them.
The cost of that freedom is a full application: income evidence, bank statements, a credit search, affordability assessed against current rules, and a valuation. There is legal work too, though on a straightforward remortgage it is much lighter than a purchase and many lenders cover it. No stamp duty either. It takes longer than the alternative, and it can be declined.
You stay put and move onto a new rate from your current lender's range. This is the quiet option, and a common one.
The appeal is speed. Usually no new valuation, no conveyancing, no full affordability reassessment and often no fee, and many lenders let you do it online in twenty minutes. Because there is no fresh underwriting in most cases, it can be the only realistic route if your income has become harder to evidence.
The catch is that you are choosing from one lender's shelf. Sometimes those rates are genuinely competitive. Sometimes they are noticeably worse than the market. The question we get asked most is whether a product transfer is a cop out. It isn't. It just needs comparing against the open market rather than accepted on trust.
You let the fix expire and stay on the standard variable rate. Your payment goes up, possibly by a lot, and can change again at the lender's discretion.
One narrow case makes this reasonable: you are about to sell or repay within a few months and want no tie in. Standard variable rates are almost always free of early repayment charges, so that flexibility has value if you are genuinely about to use it. Otherwise it is an expensive way to buy time.
A rate on its own tells you very little. What matters is the total you hand over across the deal period, which means adding the fees to the interest. Work out four things for each option, over the fixed period rather than the full term:
Here is why this changes answers. Say one deal is 4.35% with a £1,499 fee and another 4.55% with no fee, on a £180,000 balance over two years. The lower rate saves roughly £360 a year in interest, about £720 across the fix, against that £1,499 fee. The fee free deal wins. On a larger balance or a longer fix the maths flips, which is the point: do the sum.
Our breakdown of what it costs to remortgage covers the fees in full. Lenders must also give you a standardised illustration showing total cost, and comparing those beats comparing adverts.
Most fixed rates carry an early repayment charge if you leave before the end of the term, commonly 1% to 5% of the balance and often stepping down each year. On £200,000 that is £2,000 to £10,000, so it is not a detail.
Find yours before you do anything else. It will be in your original mortgage offer, and your lender will confirm the figure and the date it falls away if you ask. Ask about exit or deeds release fees too, which are modest but tend to appear on the redemption statement as a surprise.
Timing matters because these charges normally end on the date your fixed period ends, and a new deal can be arranged to complete the day after. Miss one side and you pay a penalty. Miss the other and you pay standard variable rate interest. Getting those two dates to meet is most of the value in starting early.
Occasionally paying the charge is still cheaper, if the rate saving over the remaining years outweighs it. That is a calculation, not a rule of thumb.
A lender assesses you as you are now, not as you were five years ago.
If you have dropped hours, moved to a lower paid role, or gone from employed to self employed, a new lender will reassess affordability against current criteria. Two years of accounts is the usual expectation for self employed applicants, though some lenders consider one year and a few take a more generous view of retained profit. If the numbers no longer stretch far enough, a product transfer is often still available, because you are not asking to borrow more.
A missed payment or a default narrows your options rather than closing them. Get your own credit report first so you know what a lender will see, and check the dates, because most adverse credit carries less weight as it ages. A product transfer generally avoids a fresh credit assessment, which makes it the pragmatic route meanwhile.
Your loan to value drives which rates you can reach, and the bands matter. Dropping below 80% or 75% can move you into a better tier, and five years of capital repayments plus any price growth may have done that without you noticing. It works the other way on a flat market, particularly on a new build bought at a premium. A loan to value calculator tells you which shelf you are shopping from.
Fixing buys certainty. Your payment stays the same for the period you choose, which is worth a lot if your budget is tight. You pay for that in two ways: the rate is usually a little higher than the equivalent tracker, and you are tied in with an early repayment charge.
A tracker follows the base rate plus a set margin. If the base rate falls, your payment falls, usually within a month or two. If it rises, it rises. Many trackers carry no early repayment charge, which suits anyone who might move soon.
The honest position on which is better: nobody knows. Through 2025 the market priced in cuts. As of mid 2026 the live debate is whether the next move is up rather than down, with three of the nine MPC members voting to raise at the July meeting and CPI inflation at 2.6%, above target. Anyone confident about where the base rate goes next is guessing.
What you can decide is how much uncertainty you can absorb. If a £200 a month rise would genuinely hurt, fix, and stop reading forecasts. If you have headroom and a reason to keep flexibility, a tracker is defensible. Our comparison of fixed versus tracker mortgages covers both.
If your fixed rate has six months or less to run, that is the moment to get someone to look at it properly: your early repayment charge, your loan to value, what your current lender is offering, and what the wider market would offer instead. It is a couple of hours' work, and the difference between a managed change and an expensive drift onto the standard variable rate.
We are regulated, which you can check on the Financial Conduct Authority register, and we look at both the open market and your existing lender's retention range. Get in touch and we will tell you plainly whether moving is worth it or whether staying put is better in your case.
