Mortgages

Are Mortgages Portable? What Porting Really Means When You Move Home

If you are moving home, you may be able to take your mortgage with you, but it is not guaranteed. Most UK mortgages are portable, however you still have to reapply, meet current lending rules, and get the lender’s approval. Porting keeps your existing rate, but extra borrowing usually goes on a new deal and early repayment charges can still apply in some cases. Before deciding, compare porting against switching mortgages, as changing lender can sometimes be cheaper and simpler long term.

Will Sharman

Dec 15, 2025

Are Mortgages Portable?

Short answer: yes, many mortgages are portable.
Real answer: porting is not guaranteed, you still have to reapply, and in some cases switching mortgages is the smarter move.

If you are moving home and wondering whether you can take your mortgage with you, this guide explains how mortgage porting works, when it makes sense, when it does not, and the mistakes that catch people out.

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What does it mean if a mortgage is portable?

A portable mortgage allows you to move your existing mortgage deal to a new property when you move home.

You keep the same interest rate and product terms on the amount you port, but the lender treats this as a new application, not a simple transfer.

Important point most people miss:
You are not moving the loan itself. You are applying for a new mortgage with the same deal.

That is why porting can be refused.

Are all mortgages portable?

No.

Most standard residential mortgages are portable, but there are exceptions, including:

Some buy to let mortgages
Specialist or niche lenders
Older mortgage products
Certain discounted or promotional deals

Always check your original mortgage offer or ask your lender directly. If the word “portable” is not clearly stated, assume it may not be allowed.

How does porting a mortgage work step by step?

This is the process in simple terms:

You sell your current property
You find a new property
You apply to port your mortgage deal
The lender reassesses your income, credit, and outgoings
The new property is valued
The lender decides whether to approve the port

If anything has changed since you last applied, such as income, job type, debts, or property type, it can affect the outcome.

Can a lender refuse to let you port?

Yes. This is one of the biggest misconceptions.

A lender can refuse porting if:

Your income has dropped
You have become self employed
Your credit score has worsened
Your outgoings have increased
Lending rules have tightened
The new property does not meet criteria

Even borrowers with perfect payment history can be declined.

This is why checking affordability early matters, especially if you are upsizing.

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What if I need to borrow more when I move?

This is very common.

If your new home costs more than your current one, you usually:

Port your existing mortgage balance on the old rate
Take out additional borrowing on a new rate

This creates two mortgage parts, often with different end dates and interest rates.

That extra borrowing is assessed under current lending rules, not the rules from when you first took your mortgage.

Can I port my mortgage to a cheaper property?

Yes, but there is a catch.

If you move to a cheaper home and need a smaller mortgage, you may have to repay part of your loan. That repayment can trigger an Early Repayment Charge on the portion you do not port.

This is called a partial port.

Some lenders refund the charge if the purchase completes quickly. Others do not.

Always check before assuming downsizing is penalty free.

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What fees should I expect when porting?

Porting does not mean free.

You may still pay:

Valuation fees
Legal fees
Broker fees if you use one
Early Repayment Charges in some scenarios

You usually avoid a new arrangement fee on the ported part, but not always on additional borrowing.

When does porting make sense?

Porting is usually worth considering if:

You are on a very low fixed rate
You are mid deal with high exit penalties
Your circumstances are stable
You are borrowing a similar amount

In these cases, keeping the rate can save a lot of money.

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When is switching mortgage often better?

Switching can be smarter if:

Current rates are lower than your deal
You need significant extra borrowing
Your deal is ending soon
Porting creates complex split mortgages
Your lender’s new rates are uncompetitive

This is where people often lose money by defaulting to porting without doing the maths.

Porting vs switching, quick comparison

Porting

Keep existing rate
Still need lender approval
Can involve split mortgages
May still include fees

Switching

Access whole of market rates
One clean mortgage
May trigger exit charges
Often simpler long term

If you are unsure which route is cheaper, run both options through a calculator and then sanity check the numbers with an adviser.

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Common porting mistakes to avoid

Assuming portability means guaranteed approval
Not checking ERC rules on partial ports
Ignoring split mortgage end dates
Waiting too late to apply
Not comparing against market rates

These are the mistakes that cost people thousands.

What should you do next?

Before committing to a purchase:

Check if your mortgage is portable
Review your current rate and exit charges
Run porting vs switching numbers
Get advice before locking anything in

If you are moving for the first time or need help understanding your options, our first time buyer team can also help explain the process clearly:
https://www.mbnm.co.uk/services/first-time-buyers

If you are reviewing deals or borrowing again, see our remortgage advice here:
https://www.mbnm.co.uk/services/remortgage

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Final word

Most mortgages are portable.
That does not mean porting is always the right move.

Treat porting as one option, not the default. Do the maths, check the rules, and make sure the decision fits your next five years, not just the next move.

If you want help comparing the numbers properly, speak to someone who looks at the full market, not just your current lender.

Your home, your call.

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