Should you remortgage or port your mortgage when moving home?

Should you remortgage or port your mortgage when moving home?

When you’re moving home, you usually have two broad mortgage routes: porting your existing deal to the new property, or remortgaging by taking out a new mortgage (with your current lender or a different one).

The “right” option depends less on what’s popular and more on the details of your current mortgage, your move timeline, and how much you need to borrow for the new home.

This guide explains the differences, the typical pros and cons, and the factors that often influence the outcome.

What does it mean to port a mortgage?

Mortgage porting is when you keep your existing mortgage deal and transfer it to your next property—subject to your lender’s approval.

Porting is most commonly considered when you’re on a fixed rate or tracker that you’d rather not give up, and you want to avoid the costs that can come with leaving your current deal early.

Potential advantages of porting

• You may keep your current interest rate (for the portion you’re porting)
• You may reduce or avoid early repayment charges that could otherwise apply if you fully redeemed the mortgage
• You may keep the same mortgage “structure” for the part that’s being moved

Potential drawbacks of porting

• Your lender must approve the new property and the new borrowing amount
• You still need to meet affordability requirements for the new mortgage position
• If you need to borrow more, the additional amount is often handled differently (for example, it may be priced separately)
• Porting isn’t available with every lender and every deal, and the conditions can vary

Note: Porting is not the same as “guaranteed approval”. Even if you keep your existing deal, lenders still assess the new property and your circumstances.

What is remortgaging when moving home?

Remortgaging means ending your current mortgage (or switching it) and arranging a new mortgage.

This could be with the same lender or a different one. For many home movers, remortgaging is the route that offers the most flexibility—especially if they want to change lender, product type, or repayment structure.

Potential advantages of remortgaging

• More choice of lenders and products
• Opportunity to restructure the mortgage term or repayment type (where appropriate)
• A clearer path if your borrowing needs have changed since you took out your original mortgage

Potential drawbacks of remortgaging

• Early repayment charges may apply if you leave your existing deal before the end of the term
• A full application process is usually required, including credit and affordability checks
• Costs may be involved, such as valuation and legal fees, depending on the circumstances

The decision factors that matter most

1) Early repayment charges (ERCs) and deal end dates

If you’re on a fixed deal, ERCs can be a major cost driver. Porting may help you avoid some charges because you’re not necessarily redeeming the mortgage in the usual way.

If you’re close to the end of your term, remortgaging can sometimes be simpler and more cost-effective—particularly if ERCs are low or won’t apply.

2) How much you need to borrow for the new home

Moving to a more expensive property often means upsizing your loan.

• With porting, your lender may allow the existing portion to move, but any top-up may be priced separately.
• With remortgaging, you’re effectively arranging the full mortgage position again, which can be helpful if the overall borrowing picture has changed.

Moving to a cheaper property can also affect the outcome, because the portion you don’t port may need to be handled differently.

3) Affordability and credit checks

Even when porting, lenders typically reassess the mortgage position for the new property. Changes in income, spending commitments, or credit profile can affect what’s possible.

Remortgaging generally involves a full underwriting process, so it’s important to expect similar checks—applied to a new mortgage arrangement.

4) Interest rate and product flexibility

Porting can be attractive if your current deal is favourable and you want to keep it.

Remortgaging may be more suitable if you want to:

• switch lender
• move to a different product type
• adjust the mortgage term
• potentially improve the overall cost of borrowing (depending on available deals at the time)

5) Timing and move logistics

Your move timeline can influence which option is practical.

• If you’re selling and buying at different times, you may need to consider how quickly the new purchase completes.
• Porting is subject to your lender’s process and timeframes.

If your chain is complex or completion dates are uncertain, it’s worth thinking early about what your lender will require.

Common scenarios: porting vs remortgaging

Moving to a more expensive home

Porting may work if your lender agrees to the new mortgage amount and the new property meets their requirements. If you need extra borrowing, the “top-up” portion may not receive the same terms as the ported deal.

If the lender won’t support the full amount through porting, remortgaging may be the more workable route.

Moving to a lower-value home

Porting can still be possible, but the portion that isn’t needed for the new property may be handled differently. Depending on your current deal, leaving part of the mortgage behind can bring ERC considerations.

Wanting to change lender

Porting generally means staying with your existing lender for the ported portion. If switching lender is a priority, remortgaging is usually the route that enables that.

Questions worth asking before you decide

• What part of the mortgage can be ported, and what happens to any top-up?
• Are there early repayment charges, and how are they calculated in your situation?
• Will the lender reassess affordability for the new property, and what evidence will be required?
• How does the new borrowing amount affect the overall cost and structure of the mortgage?
• What are the practical timing requirements for porting versus remortgaging?

Porting and remortgaging: a quick comparison

Final thoughts

Porting and remortgaging can both be sensible choices, but they’re not interchangeable.

A good starting point is to compare:

• the cost impact of leaving your current deal (including any ERCs)
• the overall borrowing amount needed for the new property
• how your affordability and credit position may change
• whether you need flexibility (such as switching lender or restructuring the mortgage)

If you’re unsure which route fits your move, the most effective approach is to review your current mortgage terms and the likely options for your new purchase early—before you commit to a completion date.