A Joint Borrower Sole Proprietor mortgage, often shortened to a JBSP mortgage, can help people buy a home when their income alone is not enough to meet a lender’s affordability requirements. This type of mortgage is particularly popular with first-time buyers receiving support from parents or other family members.
At Key Mortgage Advice, our team can help you understand how Joint Borrower Sole Proprietor mortgages work, which lenders may consider this type of application, and whether a JBSP mortgage could be suitable for your circumstances.
Quick Answer: What Is A Joint Borrower Sole Proprietor Mortgage?
A Joint Borrower Sole Proprietor mortgage allows more than one person to be named on the mortgage while only one person owns the property. The person buying the home is the sole proprietor and is the only person named on the title deeds.
The supporting borrower’s income can be included in the lender’s affordability assessment, which may help the main borrower access a higher mortgage amount. However, all borrowers named on the mortgage share responsibility for the repayments.
Last reviewed: June 2026. Lender criteria and product availability can change. This guide is for general information only and should not be treated as personalised mortgage advice.
Which Banks Offer Joint Borrower Sole Proprietor Mortgages?
A number of UK banks, building societies and specialist lenders may offer Joint Borrower Sole Proprietor mortgages, although criteria can vary significantly between providers.
Some lenders that have offered JBSP mortgage options include:
| Lender | May Offer JBSP Mortgages? | Typical Supporting Borrowers | Key Points |
|---|---|---|---|
| Barclays | Yes | Typically close family members | Often used for family-assisted purchases where the supporting borrower is not named on the deeds. |
| Bank of Ireland | Yes | Family members | Offers family-supported mortgage options subject to affordability and lending criteria. |
| Metro Bank | Yes | Family members | May consider applications where a supporting borrower helps strengthen affordability. |
| Skipton Building Society | Yes | Family members and, in some cases, other applicants | Well known for supporting first-time buyers and family-assisted borrowing. |
| Bath Building Society | Yes | Family members | Offers family-assisted mortgage solutions assessed on an individual basis. |
| Family Building Society | Yes | Family members | Specialises in family-supported lending arrangements. |
| Principality Building Society | Yes | Family members | JBSP options may be available depending on circumstances and affordability. |
| Newcastle Building Society | Yes | Family members | Family-assisted applications may be considered subject to current criteria. |
| Suffolk Building Society | Yes | Family members and other applicants | Can consider more complex family-supported mortgage cases. |
While several lenders offer Joint Borrower Sole Proprietor mortgages, there is no single “best” option. One lender may be more suitable for a first-time buyer with parental support, while another may be better suited to a borrower with a larger deposit or more complex income.
The most suitable lender will depend on factors such as income, deposit size, credit history, age and the relationship between the borrower and supporting applicant. This is one reason many buyers choose to speak to a mortgage adviser before applying directly to a lender.
Need Help Finding A JBSP Mortgage Lender?
Joint Borrower Sole Proprietor mortgage criteria can vary from lender to lender. A mortgage broker can help you understand which lenders may consider your circumstances before you submit an application.
Our advisers can review your situation, explain what lenders may look for and help you compare suitable JBSP mortgage options.
What Is A Joint Borrower Sole Proprietor Mortgage?
A Joint Borrower Sole Proprietor mortgage allows multiple people to be named on the mortgage while only one person owns the property.
The person purchasing the home is the sole proprietor and is the only person named on the title deeds. The supporting borrower contributes to the affordability assessment and shares responsibility for the mortgage, but does not own the property.
A common example is a parent helping their child buy a first home. The parent’s income may be included in the affordability assessment, allowing the buyer to borrow more than they could alone.
For buyers struggling to meet affordability requirements, a JBSP mortgage can be one of several mortgage options worth exploring.
How Does A JBSP Mortgage Work?
When assessing a JBSP application, lenders usually consider the income of all borrowers named on the mortgage. This can increase the amount available to borrow because the lender is looking at more than one income source.
Although the supporting borrower does not own the property, they are still legally responsible for the mortgage. If repayments are missed, all borrowers named on the mortgage may be affected.
Because of this shared responsibility, lenders often carry out affordability and credit checks on all applicants.
Who Can Be Named On A Joint Borrower Sole Proprietor Mortgage?
The exact rules depend on the lender, but supporting borrowers are often close family members.
This may include:
- parents
- grandparents
- siblings
- adult children.
Some lenders may also consider other relationships, although this varies.
Many JBSP mortgages are used by parents helping first-time buyers onto the property ladder. However, they are not exclusively for first-time buyers and can sometimes be used by home movers as well.
If you are unsure who may be accepted on your application, seeking first-time buyer mortgage advice or specialist mortgage guidance can help clarify your options.
How Much Could You Borrow With A JBSP Mortgage?
There is no single answer because borrowing amounts vary between lenders.
Factors that may influence affordability include:
- income of all borrowers
- existing financial commitments
- credit history
- deposit size
- mortgage term
- age of the supporting borrower.
A supporting borrower’s income may be included, so some applicants can access higher borrowing amounts than they would achieve on a sole application.
A useful starting point is using our mortgage calculator to check how much you could borrow, although a personalised affordability assessment will provide a more accurate picture.
What Criteria Do JBSP Mortgage Lenders Look At?
While lender criteria differs, there are several areas most providers will assess.
Income And Affordability
Lenders need to be confident that repayments remain affordable throughout the mortgage term. They will usually assess the income of all applicants alongside existing financial commitments and regular expenditure.
Deposit And Loan To Value
The size of your deposit can influence which lenders are available and how much you may be able to borrow. A larger deposit may provide access to a wider range of products.
Age And Mortgage Term
Many lenders have maximum age limits that apply at the end of the mortgage term. This can be particularly important where parents or grandparents are supporting the application.
Credit History
All applicants are likely to undergo credit checks. Previous missed payments, defaults or other adverse credit issues may affect lender choice.
If credit history is a concern, our guide on adverse credit may be a useful starting point.
Independent Legal Advice
Some lenders may require supporting borrowers to obtain independent legal advice before completion. This helps ensure everyone understands their responsibilities.
Exit Strategy
Lenders often want to understand how the supporting borrower may eventually be removed from the mortgage. This could involve the main borrower increasing their income, reducing the mortgage balance or remortgaging in the future.
Pros And Cons Of Joint Borrower Sole Proprietor Mortgages
Like any mortgage product, JBSP mortgages have advantages and disadvantages.
Potential Benefits
- may increase borrowing potential
- can help first-time buyers access home ownership sooner
- supporting borrowers do not usually own the property
- may provide an alternative to gifting large sums of money.
Things To Consider
- all borrowers remain responsible for repayments
- missed payments can affect everyone named on the mortgage
- age limits may restrict available lenders
- future remortgaging may be required to remove supporting borrowers.
Understanding both sides of the arrangement is important before proceeding.
JBSP Mortgage vs Joint Mortgage vs Guarantor Mortgage
Joint Borrower Sole Proprietor mortgages, joint mortgages and guarantor mortgages are often confused, but they work differently.
| Mortgage Type | How It Works | Who Owns The Property? |
|---|---|---|
| Joint Borrower Sole Proprietor Mortgage | Multiple people are named on the mortgage, but only one person owns the property. | The sole proprietor only. |
| Joint Mortgage | Multiple people are named on both the mortgage and the title deeds. | All owners named on the title deeds. |
| Guarantor Mortgage | A guarantor supports the mortgage by agreeing to cover repayments if the borrower cannot. | Usually the main borrower. |
For many buyers, a JBSP mortgage can act as a modern alternative to older guarantor mortgage structures.
Does A JBSP Mortgage Affect Stamp Duty?
One reason JBSP mortgages are popular is that the supporting borrower is not normally added to the title deeds. This can be relevant where the supporting borrower already owns property.
Stamp Duty Land Tax rules can be complex and depend on individual circumstances. Anyone concerned about potential tax implications should seek appropriate professional advice.
You can email our team at enquiries@keymortgageadvice.co.uk if you would like to discuss your mortgage options.
Can You Remove Someone From A JBSP Mortgage Later?
Yes, in many cases a supporting borrower can be removed later. This often happens through a remortgage once the main borrower can meet affordability requirements on their own.
The lender will need to be satisfied that the remaining borrower can support the mortgage without assistance. The exact process depends on the lender and the borrower’s circumstances at the time.
Do You Need A Mortgage Broker For A JBSP Mortgage?
You are not required to use a mortgage broker, but many applicants choose to.
JBSP criteria can vary considerably between lenders. One lender may accept a particular relationship or affordability profile while another may not.
A broker can help identify suitable lenders, explain eligibility requirements and avoid applications that are unlikely to meet criteria.
At Key Mortgage Advice, our team regularly helps buyers compare family-assisted mortgage options and understand which lenders may suit their circumstances.
You can speak to our mortgage brokers in Preston, Southport or Garstang for practical support.
Speak To A JBSP Mortgage Adviser
Every Joint Borrower Sole Proprietor mortgage application is different. The most suitable lender will depend on factors such as income, age, deposit size, credit profile and long-term plans.
At Key Mortgage Advice, we help clients understand their options and compare lenders across the market. Whether you are a first-time buyer looking for family support or a parent exploring ways to help a child purchase their first home, we can explain the options available.
Joint Borrower Sole Proprietor Mortgage FAQs
What Is A Joint Borrower Sole Proprietor Mortgage?
A Joint Borrower Sole Proprietor mortgage allows more than one person to be responsible for the mortgage while only one person owns the property.
Which Banks Offer Joint Borrower Sole Proprietor Mortgages?
Several UK lenders may offer JBSP mortgages, including banks, building societies and specialist lenders. Availability and criteria can change over time, so it is worth checking your options before applying.
Do All Banks Offer JBSP Mortgages?
No. Joint Borrower Sole Proprietor mortgages are offered by selected lenders and not every bank provides this type of arrangement.
Can Parents Help With A JBSP Mortgage?
Yes. Parents are among the most common supporting borrowers on Joint Borrower Sole Proprietor mortgages, especially where a first-time buyer needs help meeting affordability requirements.
Can Grandparents, Siblings Or Friends Help With A JBSP Mortgage?
Some lenders may allow grandparents, siblings or other applicants to support a JBSP mortgage, although eligibility varies and lender criteria should always be checked.
How Many People Can Be On A JBSP Mortgage?
The maximum number of applicants depends on the lender and the product available at the time of application.
Does A JBSP Mortgage Affect Credit Score?
All borrowers named on the mortgage share responsibility for repayments. Missed payments could affect the credit records of everyone involved.
Do You Need Independent Legal Advice For A JBSP Mortgage?
Some lenders may require supporting borrowers to obtain independent legal advice before completion. This helps ensure everyone understands the responsibilities involved.
Is A Joint Borrower Sole Proprietor Mortgage Only For First-Time Buyers?
No. Although commonly used by first-time buyers, some lenders may consider JBSP mortgages for other circumstances, including home movers.
Do I Need A Mortgage Broker For A JBSP Mortgage?
No, but professional mortgage advice can help you compare lenders and understand which options may suit your circumstances. This can be useful because JBSP criteria can vary significantly between lenders.
Need Help With A JBSP Mortgage?
If you are considering a Joint Borrower Sole Proprietor mortgage, speak to Key Mortgage Advice before applying. We can help you understand your position, compare lender criteria and approach suitable lenders.
Email enquiries@keymortgageadvice.co.uk, book an appointment online or call your local office:
