Start looking 4–6 months before your current deal ends. You have two real options: a product transfer (a new deal with your existing lender, usually faster and with less paperwork) or a full remortgage (switching to a new lender, which opens up the whole market but takes longer). Doing nothing means falling onto your lender's Standard Variable Rate, which averaged over 7% in August 2026 — well above typical fixed rates.
Why timing matters more than almost anything else here
Most lenders will let you lock in a new deal with them (a product transfer) around three to four months before your current one ends, and let you arrange a full remortgage with a new lender up to six months ahead. Crucially, agreeing a new rate in advance doesn't usually cost you anything extra, and most offers stay valid for three to six months — so there's little downside to starting early and comparing your options, then simply not proceeding if something better appears closer to your actual end date.
What does have a real cost is doing nothing. If your deal ends and you haven't arranged anything, you're automatically moved onto your lender's Standard Variable Rate (SVR) — a rate the lender sets and can change at will. As of August 2026, the average SVR sits above 7%, compared to average fixed rates around 5.6%. On a £200,000 mortgage, that gap alone can add several hundred pounds a month.
Product transfer vs full remortgage: what's actually different
| Product transfer | Full remortgage | |
|---|---|---|
| What it is | A new deal with your current lender | Switching your mortgage to a new lender |
| Speed | Usually fastest — often no new valuation or full underwriting | Typically 4–8 weeks, involves a fresh application |
| Affordability re-check | Often skipped or lighter-touch | Full affordability and credit assessment required |
| Rate access | Limited to what your existing lender currently offers | Access to the whole market |
| Best for | Your circumstances have changed and you might struggle to pass a new lender's checks, or you just want simplicity | Your credit and income are strong and you want to compare the whole market for the best rate |
These aren't mutually exclusive — the sensible approach is usually to get a product transfer quote from your current lender as a "baseline" and compare it against what a broker can find elsewhere. If the market beats your lender's offer, remortgage; if not, the product transfer is often quicker and less hassle.
When a full remortgage is worth the extra effort
- Your property has gone up in value, or you've paid down a chunk of the balance — this can move you into a lower loan-to-value band with a different lender, unlocking meaningfully better rates than your existing lender's own product transfer offers.
- You want to borrow more — for home improvements, debt consolidation or another purpose — and the market offers better terms than your current lender's further-borrowing rate.
- Your current lender's product transfer rates are uncompetitive — lenders don't have to offer their existing customers their best rates, so it's always worth checking.
When a product transfer is the safer choice
- Your income or circumstances have changed since you took out your current mortgage — self-employment, a career change, a new dependant, or simply tighter finances. A full remortgage means a fresh affordability check under today's rules; a product transfer is often lighter-touch.
- You're close to the end of your term or your circumstances are complex and you'd rather avoid the paperwork of a full new application.
- You just want the simplest, fastest route and your existing lender's rates are already competitive.
If you switch — to a product transfer or a new lender — before your current deal actually ends, you'll usually trigger an early repayment charge (ERC), typically a percentage of your outstanding balance that steps down the closer you get to your deal's end date. Run the numbers: sometimes the new rate saves you more than the ERC costs, but always check before committing.
How to actually start the process
- Mark your deal end date and set a reminder for 6 months before.
- Get a product transfer quote from your current lender — many show this in your online account with no impact on your credit file.
- Compare against the open market, either yourself or through a whole-of-market broker, using the same rate, term and any fees for a fair comparison.
- Lock in whichever is better, keeping in mind most offers are valid for months, so you can often revisit if rates move before completion.