Moving home sounds simple on paper, but it can quickly turn into a juggling act. You may have found a new place, worked out the deposit, and started thinking about removals, only for someone to mention “porting your mortgage”.
Porting can be a useful option, especially if you are on a fixed rate you would rather not lose. But it is not automatic, and it is not guaranteed just because your current mortgage offer says the product is portable. Before you build your moving plans around it, there are a few important checks to make.
What porting actually means
In plain English, porting means moving your existing mortgage product, usually the interest rate and remaining deal period, across to your new property when you move home.
You are not simply transferring the old loan from one property to another. In most cases, you are making a new mortgage application with your existing lender, secured against the new property. The lender will reassess you, value the new home, and decide whether the new mortgage meets its current criteria.
That subtle difference matters, because it is the part that catches people out. A mortgage can be portable in principle, but your application still needs to be approved. Speaking to a mortgage broker early can flag any issues before you put your current home on the market.
Will your lender actually let you?
Many UK mortgage products are portable, but the rules vary by lender and product. Before you do anything else, check your original mortgage offer, product terms, or lender portal to see whether porting is allowed.
A few points are worth checking early:
- Some products cannot be ported.
- You will usually need to pass a fresh affordability assessment.
- The new property must meet the lender’s valuation and lending criteria.
- Porting may need to happen within a set timeframe after selling.
- If you need to borrow more, the extra borrowing will usually be on a new product at today’s rates.
If you are not sure where to start, the mortgages overview is a sensible place to read up on your options. The jargon buster is also useful for terms such as ERC, LTV and sub-account.
You will be reassessed all over again
This is where porting trips up many homeowners. Your lender will normally apply today’s affordability rules, not the rules that applied when you first took out the mortgage.
Even if you have never missed a payment, the lender will look again at your income, outgoings, credit commitments, loan-to-value and the new property. Changes since your last application can matter, including a new job, self-employment, car finance, childcare costs, reduced income, maternity leave, debts or a change in credit score.
A few practical steps can help:
- Avoid taking on large new credit commitments before applying.
- Check your credit file and correct any errors.
- Keep bank statements tidy.
- Gather payslips, accounts, ID and proof of deposit early.
- Speak to a broker before making an offer if your finances have changed.
Our buyers advice section runs through what lenders look at and how to put your best foot forward.
When porting makes sense, and when it does not
Porting tends to make most sense when your current rate is lower than the deals available today, or where leaving your mortgage would trigger a large early repayment charge.
There are 3 common scenarios.
If you are borrowing the same amount, porting is usually the cleanest option. If your lender agrees and the sale and purchase fit the porting rules, you may avoid an early repayment charge.
If you are borrowing more, you usually keep your existing product on the amount you port and take a new deal for the extra borrowing. This can leave you with 2 parts to the same mortgage, often called sub-accounts, with different rates and end dates.
If you are borrowing less, you may pay an early repayment charge on the part of the mortgage you do not take with you. For example, if you currently owe £250,000 but only port £200,000, the unported £50,000 may be treated as an early repayment.
Early repayment charges vary by lender and product, but they are often a percentage of the amount being repaid during a fixed or discounted period. On larger mortgages, this can be a significant cost, so it needs to be included in the comparison.
If you are considering staying put instead, a straightforward remortgages conversation may help you see whether moving and porting really stacks up.
Watch out for the timing trap
Timing is one of the most overlooked parts of porting. Some lenders allow a gap between selling your old home and completing on the new one, but the window varies. It may be a few months, and some lenders require the porting application to be submitted before the old mortgage is redeemed.
In some cases, the lender charges the early repayment charge when you sell and refunds it if the new mortgage completes within the allowed porting window. Other lenders handle it differently.
That is why the dates matter. If you sell, repay the mortgage in full, and then wait too long before buying again, the porting option may no longer be available.
If you are in a chain, getting your conveyancing instructed promptly is one of the best ways to keep the dates aligned.
Do not forget the other moving costs
A house move is about more than the mortgage. You may need to budget for stamp duty, legal fees, valuations, surveys, removals, broker fees and any product or arrangement fees.
You will usually need buildings cover in place from exchange of contracts if you are buying a freehold property, and lenders generally require suitable cover before completion. It is also sensible to revisit your home insurance, life insurance, critical illness cover and income protection if your mortgage balance, term or family circumstances are changing.
For more on the wider home-move process, our home mover mortgages page explains how the pieces fit together.
Frequently asked questions
Is porting my mortgage guaranteed if my deal allows it?
No. Even if your mortgage product is portable, you still need to pass your lender’s current affordability checks, and the new property must meet its lending criteria.
Will I pay an early repayment charge if I port?
Usually not on the amount you successfully port, provided you complete within your lender’s porting rules. If you borrow less, or miss the porting window, an early repayment charge may apply.
Can I borrow more when I port my mortgage?
Often, yes. You usually keep your existing rate on the amount you port and take a new product at current rates for the extra borrowing.
What happens if I sell before I find a new place?
Some lenders allow a gap and may refund an early repayment charge if you complete the new mortgage within their window. The exact rules vary, so check before selling.
Is porting always cheaper than getting a new mortgage?
Not always. If your current rate is much lower than today’s deals, porting may help. But if rates have fallen, or the early repayment charge is small, a new mortgage may work out better. Compare the full cost, not just the rate.
Ready to find out if porting works for you?
Porting can save money, but only if the numbers genuinely stack up for your move. Before you put your home on the market, get a quick sense-check. Call our team on 020 7183 0212 or send a mortgage enquiry, and we will give you honest, straightforward advice on whether to port your existing deal or start fresh with something new.
Your home may be repossessed if you do not keep up repayments on your mortgage.
