What does it mean to port a mortgage when moving house?

Full answer

Mortgage porting is a feature offered by many (though not all) mortgage lenders that allows borrowers to move house without having to fully repay their existing mortgage deal and start again with a brand new one, which can save a significant amount in early repayment charges. **Why porting matters -- avoiding early repayment charges** Most fixed-rate and many tracker mortgage deals carry early repayment charges (ERCs) if you repay the mortgage in full before the deal's fixed or introductory period ends -- these can amount to several percent of the outstanding balance. Porting lets you keep the same deal (and avoid triggering the ERC) by transferring it to a new property, rather than redeeming the old mortgage and taking out an entirely new one elsewhere. **How porting actually works** Technically, porting involves redeeming the existing mortgage on the sale of your current property and simultaneously taking out a new mortgage on the new property with the SAME lender, on the SAME (or equivalent) rate and terms -- from the lender's perspective, it's treated as a continuation of the existing deal rather than as new borrowing subject to the ERC, provided the timing and lender's specific conditions are met. **You still need to pass affordability checks again** Porting isn't automatic -- you'll need to reapply and pass the lender's current affordability and credit assessment for the new property, even though you're "keeping" the same rate. This matters because your circumstances (income, other debts, credit history) may have changed since you first took out the mortgage, and the lender's current lending criteria might also have tightened, meaning porting isn't guaranteed even if you want to use it. **Borrowing more if the new property costs more** If the new property is more expensive than your current one, the ported amount alone usually won't cover the full purchase price -- you'll typically need to borrow the additional amount through a top-up loan, which is usually arranged at the lender's CURRENT interest rate for that portion, rather than your original ported rate. This means your overall mortgage often ends up as a blend of the old ported rate (on the original portion) and a new rate (on the additional borrowing). **If the new property costs less** Conversely, if you're downsizing and need to borrow less than your current mortgage balance, you may still face an early repayment charge on the portion you're not porting across, since you're still technically repaying part of the original loan early -- check your specific mortgage's terms on partial porting and any ERC that might still apply to the reduced amount. **Timing can be tricky** Porting generally requires the sale of your old property and the purchase of the new one to complete on the same day (or very close together), since the mortgage is being redeemed and re-advanced almost simultaneously -- this can add pressure to an already complex property chain, and it's worth discussing timing carefully with your lender, solicitor, and mortgage broker well in advance. **Not all mortgages are portable** Portability is a specific feature that isn't offered on every mortgage product -- always check your mortgage offer documents or ask your lender directly whether your specific deal is portable before assuming you'll be able to avoid an ERC when you move. **Practical tip** If you're moving house during a fixed-rate deal, contact your current lender early to confirm whether porting is available, get a decision in principle for the combined ported-plus-top-up borrowing, and compare the total cost against simply redeeming the mortgage (paying the ERC) and remortgaging elsewhere, since a much better rate elsewhere can sometimes still work out cheaper overall despite the ERC.

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