How early can you remortgage before your deal ends?

You can start reviewing your mortgage options around six months before your current deal ends. Depending on the lender, you may be able to arrange your next deal in advance and have it start when your existing deal finishes.

The important distinction is between arranging a mortgage early and starting it early. Applying ahead of time doesn’t necessarily mean leaving your current rate straight away. Your lender’s rules, the new offer’s expiry date and any early repayment charges determine how the dates fit together.

When should you start reviewing your mortgage options?

Around six months ahead is a useful point to gather your mortgage details and compare the possible routes. It’s a planning starting point, rather than a promise that every lender will let you reserve a deal then.

You can prepare earlier if your circumstances need attention, such as a change in employment, self-employed income evidence or a proposed change to who owns the property.

Understanding what happens when your fixed-rate mortgage ends helps establish the rate your mortgage is due to move onto if another deal isn’t ready.

Think about the timetable in three stages:

Stage	What you can do	What determines the timing
Review your options	Gather mortgage details and compare possible routes	You can prepare before a lender’s application window opens
Arrange the next deal	Apply to another lender or select an existing-lender product	Lender rules, eligibility and offer validity
Start the new deal	Complete the remortgage or begin the product transfer	The agreed start date, legal readiness and any charges

When we assess the timing, we’d check the fixed-rate end date and the early repayment charge expiry separately. They aren’t always the same date.

How early can you apply for a remortgage?

Remortgaging means replacing your existing mortgage with one from another lender.

The FCA explains that mortgage offers generally remain valid for three to six months after issue, depending on the lender. This can allow you to arrange a mortgage before your current deal ends.

However, the application date isn’t the completion date. The new lender still needs to assess your application and property, and legal work must be ready before the existing mortgage can be repaid.

An agreement in principle is also different from a formal mortgage offer. Don’t assume it guarantees approval or secures a particular rate.

The useful question is whether the offer will remain valid for your intended completion date.

For a hypothetical example, suppose your current deal and ERC period both end on 30 June:

• An offer expiring on 31 July might support completion on 1 July, subject to lender and solicitor confirmation.
• An offer expiring on 15 June wouldn’t cover that plan.

We’d check the actual expiry date before relying on an offer, rather than assume every lender provides six months.

How early can you arrange a product transfer?

A product transfer means taking another mortgage product with your current lender. Its reservation window can differ from the timetable for moving elsewhere.

When checked on 12 October 2026:

• Halifax allowed customers to arrange a new deal up to four months before their existing one ended. It separately described an ERC-free window for starting an existing-customer switch in the final three months.
• Nationwide allowed eligible fixed-rate customers with less than four months remaining to apply to switch. It directs customers to their individual switch and cancellation deadlines.

These are examples of each lender’s existing-customer rules. An ERC waiver for a product transfer doesn’t automatically apply when you repay the mortgage to move to another lender.

Does the Mortgage Charter guarantee a six-month window?

The 2026 Mortgage Charter describes opportunities for customers of participating lenders to secure a deal up to six months ahead. Its footnote makes clear that six months is the maximum, so you need to check your lender’s actual window.

The Charter also describes requesting an available better like-for-like deal, but its footnote says rates must be finalised two weeks before the new term starts. Don’t assume changes can be made on the final day.

These Charter commitments concern residential mortgages and don’t apply to buy-to-let.

A straightforward eligible product transfer can involve fewer checks than changing lender. Extra borrowing or changes to the term or repayment type can alter the process.

Will you pay an early repayment charge?

Submitting an application isn’t the same as repaying your existing mortgage. An early repayment charge, or ERC, may become relevant when the old mortgage is redeemed or an existing-lender product change takes effect.

There may still be application or product fees before completion.

Check your mortgage agreement and ask the lender to confirm the charge for the proposed date. The Financial Ombudsman explains that an ERC charging period can sometimes extend beyond the special-rate period.

A lower new rate doesn’t automatically justify leaving early.

For illustration, a 2% ERC on a £200,000 balance would be £4,000. Reducing your payment by £100 a month for three months would reduce payments by £300. That reduction alone wouldn’t offset the charge.

This isn’t a complete cost comparison. We’d also consider fees, interest, the balance remaining and the period over which you’re comparing the options. Lower monthly payments don’t necessarily mean lower overall borrowing costs.

What happens if rates change before your new deal starts?

If available rates rise

A valid fixed-rate offer can preserve the agreed rate, subject to its conditions. For example, Nationwide describes a six-month fixed-offer window, unless the applicant’s circumstances change.

That doesn’t make every offer unconditional. Check what has been reserved, when it expires and what changes you must report.

A tracker works differently: its rate can move with the reference rate specified in the contract. Arranging a tracker doesn’t fix its future payments.

If available rates fall

Your agreed fixed rate won’t automatically fall because a cheaper product becomes available.

Ask your broker or lender whether you can change products before the relevant deadline. The existing-lender Charter provision described above and a new-lender remortgage’s amendment process aren’t interchangeable.

Before changing an arrangement, check:

• Whether the new product is available to you.
• Any fees, refund rules or further checks.
• Whether revised documents are needed.
• Whether the change could delay completion.

We’d confirm a suitable replacement arrangement before cancelling one you’re relying on. Don’t assume that changing products is free or that the original deal can always be reinstated.

Arranging early can give you time to assess your options. It doesn’t establish that today’s rate will be the cheapest available before your current deal ends.

What if your offer expires or you leave it too late?

Contact your broker or lender before the offer expires. An extension or replacement may be possible, but it requires lender approval and could involve updated information.

If the current deal ends before your next arrangement starts, the mortgage normally continues on its contractual reversion rate. This is often an SVR, although some mortgages use another rate.

Your payments may change during that gap. Don’t assume the reversion rate is always the most expensive option, but include it in the comparison.

Keep making the required mortgage payments until your lender confirms the transition. If you’re worried about affordability, contact your lender promptly.

What should you check before arranging your next deal?

Gather:

• Your outstanding balance, repayment type and remaining term.
• The current deal-end date and confirmed ERC expiry.
• Your lender’s reservation, cancellation and start deadlines.
• Any new offer’s expiry and product-change rules.
• Your estimated property value, income and commitments.
• Changes to your circumstances and the costs of switching.

A remortgage calculator can illustrate potential repayments while you compare options. It won’t establish eligibility or the earliest date you can switch.

Our remortgage advice can help you compare moving lender with taking another product from your current lender, and check how the dates fit together.