Selling a London Property With a Mortgage: What Sellers Should Check First

Selling a London property with a mortgage is common, but there are several financial details to understand before putting your home on the market.

Your property may have increased in value since you bought it. However, the amount you could actually have left after the sale depends on more than the expected selling price.

Your outstanding mortgage, possible early repayment charges, estate agent fees, legal costs and other expenses can all affect the amount you receive.

The good news is that you can make the process easier by checking the numbers before you start.

Can You Sell a London Property If You Still Have a Mortgage?

Yes. Having a mortgage does not normally prevent you from selling your property.

When the sale completes, the mortgage secured against the property will generally need to be repaid from the sale proceeds. Your solicitor or conveyancer will normally deal with the legal and financial arrangements involved in redeeming the mortgage.

Before marketing your property, however, it is sensible to contact your mortgage lender and ask for an up-to-date statement.

This can help you understand your current position before deciding on an asking price.

You can also begin by arranging a property valuation to get a better idea of the potential market value.

1. Check Your Outstanding Mortgage Balance

The first figure to understand is your outstanding mortgage balance.

Your original mortgage amount is not necessarily the amount you still owe. Monthly repayments may have reduced the balance over time, depending on the type of mortgage you have.

Ask your lender for current information about:

• Outstanding mortgage balance
• Mortgage redemption figure
• Current interest rate
• Fixed-rate or tracker period
• Early repayment charges
• Any other charges that may apply when the mortgage is repaid

A redemption statement can give your solicitor the information needed when the sale progresses.

Do not rely on an old mortgage statement when calculating how much money you may have left after selling.

Your balance can change between the time you first investigate selling and the eventual completion date.

2. Understand Your Property Equity

Property equity is broadly the difference between the property’s current value and the amount secured against it.

For example, imagine your London property could sell for £500,000 and your remaining mortgage is £300,000.

That gives you approximately £200,000 in equity before other selling costs.

The actual amount you receive can be lower after expenses.

These may include:

• Estate agent fees
• Legal or conveyancing costs
• Mortgage repayment charges
• Removal costs
• Property preparation costs
• Other transaction-related expenses

This is why an estimated property value should not automatically be treated as the amount you will receive.

The GOV.UK guide to selling a home also recommends checking how much you owe on your mortgage and understanding the costs involved in selling.

3. Get a Realistic Property Valuation

Knowing what your property might realistically sell for is an important part of the calculation.

A valuation can help you compare the potential sale price with your mortgage balance and estimated selling costs.

However, one valuation should not necessarily be treated as a guaranteed final selling price.

The eventual sale price can be affected by buyer demand, property condition, marketing, negotiations and wider market conditions.

If you are preparing to sell, you can explore the Find My Estate Agent property services and arrange a valuation before deciding on your next step.

For more guidance about buyer behaviour, our recent article on What Buyers Look for When Viewing a Property in London explains some of the factors that can influence a buyer’s impression of a home.

4. Check for Early Repayment Charges

Some mortgages include an early repayment charge during a particular period.

This can be especially relevant if you are selling while your mortgage deal is still within a fixed or special-rate period.

The amount and conditions depend on your mortgage agreement.

Therefore, contact your lender before assuming that you can repay the mortgage without an additional charge.

Ask the lender to confirm:

• Whether an early repayment charge applies
• How much the charge could be
• When the charge ends
• Whether there are other mortgage exit fees
• How long a redemption statement remains valid

Getting this information early can prevent an unexpected cost later in the sale.

If you are unsure about your mortgage terms, speak directly with your lender or obtain independent financial advice.

5. Calculate Your Likely Selling Costs

The sale price is only one side of the calculation.

You should also consider the costs involved in completing the sale.

Potential costs can include:

Estate agent fees

Estate agents may charge different fees depending on the service and agreement.

Before choosing an agent, make sure you understand exactly what you will pay and when the fee becomes payable.

Our guide, Find My Estate Agent London: How It Works, explains how property owners can explore local agents and compare their options.

Legal costs

You will normally need a solicitor or conveyancer to handle the legal side of the sale.

Ask for a clear quotation and check what is included.

Mortgage costs

Your lender may charge an early repayment fee or other costs depending on your mortgage agreement.

Moving costs

If you are buying another property, remember to consider removal costs and other expenses connected with your next move.

Adding these figures together gives you a more realistic idea of your potential net proceeds.

6. Check Your EPC Before Marketing

An Energy Performance Certificate is another important consideration when selling a property.

In England, a valid EPC is generally required when a property is marketed for sale or rent, subject to applicable exemptions. GOV.UK states that an EPC is generally valid for 10 years.

Before arranging a new certificate, check whether your property already has a valid EPC.

You can use the official GOV.UK energy certificate service to check whether an existing certificate is available.

If you need a new certificate, you can also explore the Find My Estate Agent EPC service.

Having the EPC situation sorted early can make your preparation more straightforward.

7. Get Your Property Paperwork Ready

Mortgage information is only one part of your selling paperwork.

You may also need information relating to:

• Property ownership
• Freehold or leasehold status
• EPC
• Planning permissions
• Building regulations
• Guarantees and warranties
• Property alterations
• Leasehold information
• Service charges
• Relevant property documents

GOV.UK recommends getting important property paperwork together before putting your home on the market.

Preparing documents early can help you respond more quickly when your solicitor, estate agent or buyer requests information.

8. Do Not Set the Asking Price Based Only on Your Mortgage

One common mistake is choosing an asking price based on how much money the seller needs.

Your mortgage balance is important to you, but buyers are not pricing the property according to your mortgage.

Instead, the asking price should reflect the property’s market position.

Consider factors such as:

• Location
• Property type
• Size
• Condition
• Number of bedrooms
• Local demand
• Comparable properties
• Recent improvements
• Current competition

A professional valuation can give you a useful starting point.

If you want to understand how buyer interest can change depending on presentation and pricing, read our guide on Property Not Getting Viewings? 9 Things to Check in London.

9. Consider Your Next Property Before Selling

If you are selling your London home because you are moving elsewhere, the timing of your next purchase may affect your plans.

Some sellers need to coordinate a sale with another property purchase.

Others may sell first and rent temporarily.

There is no single approach that works for everyone.

However, understanding your mortgage position before making arrangements can help you make a more informed decision.

If you are planning to buy another property, speak with your mortgage lender or a qualified mortgage adviser about your borrowing position.

Do not assume that the equity from your current property will automatically determine how much you can borrow for your next home.

10. Keep an Eye on Your Net Sale Proceeds

A useful way to think about the sale is to estimate your potential net proceeds.

For example:

Expected sale price

minus

Outstanding mortgage

minus

Mortgage repayment charges

minus

Estate agent fees

minus

Legal and other selling costs

equals

Estimated amount left after the sale

This is only a planning calculation.

The final figure can change because the eventual sale price, mortgage redemption amount and transaction costs may differ from your initial estimates.

Still, creating a simple calculation can help you understand your position before making decisions.

A Simple Mortgage-Sale Checklist

Before putting your London property on the market, consider working through this checklist:

• Check your outstanding mortgage balance
• Request mortgage redemption information
• Ask about early repayment charges
• Arrange a realistic property valuation
• Estimate estate agent fees
• Obtain a conveyancing quotation
• Check whether your EPC is valid
• Gather important property documents
• Consider your expected moving costs
• Estimate your potential net sale proceeds
• Compare local property listings
• Choose an estate agent based on more than just price

You can also read our recent guide, What Buyers Look for When Viewing a Property in London, for practical information about the factors buyers may consider when they visit a home.

What If Your Property Value Is Lower Than Your Mortgage?

This situation can require additional care.

If the amount you owe on your mortgage is greater than the property’s likely sale price, selling the property may not be straightforward.

For example, if your mortgage balance is £350,000 but the property could only realistically sell for £320,000, there is a £30,000 difference before considering other selling costs.

This is sometimes referred to as negative equity.

If you think this may apply to your situation, speak with your mortgage lender and obtain appropriate professional financial advice before putting the property on the market.

Do not assume that a sale can proceed simply because you have found a buyer.

How Find My Estate Agent Can Help

Selling a London property involves several moving parts.

You need to understand your property’s potential value, prepare the home, organise important information and find an estate agent who can market the property effectively.

Find My Estate Agent helps London property owners explore local estate agents and supporting property services.

You can start by using Find My Estate Agent to explore your options.

The platform also provides services such as EPCs, property photography and floor plans.

If you are preparing your home for the market, you may also want to explore our property services.

Final Thoughts

Selling a London property with a mortgage does not have to be confusing.

The key is to understand your financial position before you begin.

Check your mortgage balance, ask about repayment charges, get a realistic property valuation and estimate your selling costs.

At the same time, prepare your EPC and property paperwork early.

Most importantly, remember that the property’s market value is not the same as the amount you will receive after completing the sale.

With a clear estimate of your mortgage, selling costs and expected sale price, you can approach the process with greater confidence.

For official information about selling a property in England, visit the GOV.UK guide to selling a home.

For information about checking an existing EPC, use the official GOV.UK energy certificate service.

Ready to start planning your London property sale? Explore Find My Estate Agent to discover local estate agents and property services.