Remortgaging Explained: When to Start the Process Before Your Deal Ends

Remortgaging - switching your mortgage, either with your existing lender or a new one - is one of the most valuable financial habits a homeowner can maintain, yet a significant number of borrowers still drift onto their lender’s expensive Standard Variable Rate simply through inertia. Here’s how the process actually works and the right timeline.

What remortgaging actually means

Remortgaging means replacing your current mortgage deal, either by switching to a new deal with your existing lender (sometimes called a ‘product transfer’) or by moving to an entirely new lender. People remortgage for various reasons: their current fixed or tracker deal is ending, they want to release equity, or they want better terms than their current deal offers.

The six-month window

Under the Mortgage Charter, signatory lenders (representing around 90% of the market) allow borrowers to lock in a new deal up to six months before their existing one ends, and to switch to an even better like-for-like deal right up until the new term actually starts if one becomes available (see our dedicated article on preparing for your fixed rate to end, which covers this timeline in detail).

Product transfer vs full remortgage

• Product transfer (staying with your existing lender): typically faster and simpler, often without a full new affordability assessment, but you’re limited to whatever deals your current lender offers - not necessarily the best in the market.
• Full remortgage (switching lender): usually requires a full application and affordability assessment (similar to your original mortgage application), and involves legal and valuation costs, but opens up the whole market rather than just your existing lender’s offers.

When a full remortgage is worth the extra effort

If your circumstances have improved since you last took out a mortgage - a higher income, better credit history, or your property has increased in value relative to your remaining loan (improving your loan-to-value ratio) - a full remortgage with a new lender may unlock meaningfully better rates than a product transfer with your existing one, even after accounting for the additional fees and effort involved.

Releasing equity through a remortgage

Some homeowners remortgage specifically to borrow more against their property’s increased value, releasing cash for home improvements, debt consolidation, or other purposes. This increases your total mortgage debt and monthly payments, and lenders will assess affordability for the higher amount - it’s not simply ‘free money’ from the property’s paper value, and should be weighed carefully against alternatives (such as a personal loan) depending on the amount and purpose.

What to gather before starting the process

• Recent payslips or tax returns (if self-employed - see our dedicated article on this), similar to your original mortgage application.
• A recent property valuation estimate, since your current loan-to-value ratio affects the rates available to you.
• Details of your existing mortgage, including whether it’s a repayment or interest-only mortgage (see our dedicated article on what happens at the end of an interest-only term) and any early repayment charges that might apply if you switch before your current deal technically ends.
• A clear view of your current outgoings, since affordability is reassessed for a full remortgage in the same way as an original application (see our dedicated affordability rules article).

The bottom line

Whether you choose a simple product transfer or a full remortgage with a new lender, the key is starting the process three to six months before your current deal ends - not waiting until it’s already lapsed onto an expensive Standard Variable Rate. The Mortgage Charter’s protections make this genuinely low-risk to start early, since you can still switch to something better if it appears before your new term begins.