Buying a Property

Porting a Mortgage: Can I Take My Mortgage to a New Property?

Mortgage porting lets you move your existing mortgage deal to a new property when you move home. This guide explains when it works, when it doesn’t, and the costs involved.

Published: 17 Mar 2026 · Updated: 17 Mar 2026 · 6 min read

#MortgagePorting#MovingHome#EarlyRepaymentCharge#MortgageUK#PropertyPassportUK

Porting means transferring your existing mortgage deal to a new property when you move. It allows you to keep your current interest rate and avoid the early repayment charge (ERC) that would apply if you repaid the mortgage early to take a new product.

Why Port?

If you are in the middle of a fixed rate deal, repaying it early triggers an early repayment charge — typically 1–5% of the outstanding balance. On a £250,000 mortgage in year two of a 5-year fix with a 3% ERC, that is £7,500 wasted.

Porting avoids the ERC by moving the mortgage to the new property instead of redeeming it.

How Porting Works

Porting is not automatic. You must:

1. Apply to port as if it were a new mortgage application — the lender reassesses your income, outgoings, and the new property

2. The lender values the new property

3. If approved, the existing deal transfers to the new property

The lender is not obliged to approve the port even if your deal technically allows it. If your circumstances have changed (income reduced, higher outgoings, new property outside the lender’s criteria), the port can be declined.

What Happens If You Need to Borrow More?

If the new property costs more than the existing mortgage, you will need to borrow the difference. This top-up is typically taken as a separate mortgage product at the current market rate. You end up with two mortgage parts: the ported portion on the old rate, and the top-up on a new rate.

If the new property costs less, you repay the surplus from the sale proceeds. Some lenders charge an ERC on the repaid portion even when porting — check your mortgage terms carefully.

Porting: The Hidden Complications

**New application:** A full affordability assessment is required even though you are technically keeping the same mortgage
**Valuation:** The new property must meet the lender’s criteria (e.g. no above-a-shop flats, no very short leases, no unusual construction)
**Timing gap:** If you complete on the sale before you complete on the purchase, there may be a gap where the mortgage is technically redeemed. Some lenders allow a 90-day window; others do not
**Declined ports:** If the port is declined, you face the ERC and must remortgage elsewhere

Port vs Remortgage: A Comparison

Scenario	Port	Remortgage
Mid-fixed-term, competitive rate	Better — avoids ERC	Worse — ERC applies
End of fixed term, new deal available	Either works	Potentially better rate available
Significant increase in borrowing needed	Complicated top-up structure	Cleaner single new deal
Lender criteria no longer fits	Not possible	Freedom to switch lender

When Not to Port

Porting is not always the right choice:

If your current rate is higher than new deals available in the market, paying the ERC to remortgage to a better deal can pay for itself within 1–2 years
If the lender’s new borrowing rate on the top-up is uncompetitive
If your circumstances have changed in ways that might cause the port to be declined anyway

Always calculate the full cost — ERC vs interest savings — before deciding whether to port or remortgage.