What does it mean to port a mortgage when I move house?

Full answer

Porting is a valuable feature for homeowners who move house while still within a fixed or discounted mortgage deal period, letting them keep favourable existing terms rather than facing an early repayment charge. **Why porting matters** Most fixed-rate and many discounted-rate mortgage deals carry an early repayment charge (ERC) if you exit the deal before the fixed or discount period ends -- often a percentage of the outstanding balance, which can run into thousands of pounds. Porting avoids triggering this charge by transferring the same deal to your new property instead of technically "repaying" the old mortgage. **It's not automatic -- you must reapply** Porting is not simply moving the paperwork -- you must go through a fresh application and affordability assessment for the new property, since the lender needs to confirm both your current financial circumstances and the new property meet their lending criteria, just as if you were a new applicant. If your circumstances have changed (income reduced, new debts, etc.), you might not be approved to port even though you were previously an acceptable borrower. **Borrowing more on top** If your new property costs more than your old one and you need to borrow additional funds, the ported (original) portion keeps its existing rate, but the additional borrowing is usually arranged as a new, separate part of the mortgage at the lender's current rates -- so you effectively end up with a mortgage made up of two parts with potentially different rates. **Timing considerations** Porting generally requires your old property sale and new property purchase to complete on the same day (or within a short window defined by the lender's specific rules), which can add pressure to coordinating a chain -- if the timing does not align, you may lose the ability to port and could face the early repayment charge after all. **Not all mortgages are portable** Check your specific mortgage terms, since not every product allows porting -- if yours does not, or if a new lender offers a significantly better rate that outweighs the ERC cost, it may be worth paying the charge and remortgaging fresh instead. **Worked example** Someone has 18 months remaining on a five-year fixed rate mortgage with a 3% early repayment charge (on a £200,000 balance, that would be a £6,000 charge). By porting the mortgage to their new £280,000 property (borrowing an extra £30,000 at the lender's current rate for that portion), they avoid the £6,000 charge entirely on the original £200,000 portion. **Practical tip** Contact your current lender early in your house-moving process to confirm porting eligibility and understand the process and timeline required, since leaving this until close to your target completion date can create unnecessary stress and risk missing the porting window.

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