Joint Borrower Sole Proprietor Mortgage
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Joint Borrower Sole Proprietor Mortgage (Part 1)
Adam Nunn and Jon Porter explain how a Joint Borrower Sole Proprietor mortgage works.
What is a Joint Borrower Sole Proprietor (JBSP) mortgage and how do they work?
Adam: This essentially means a joint mortgage with sole ownership. Typically, a family member or a friend agrees to go on a mortgage with you to help you borrow more money, but they will not have any ownership of, or interest in, the property.
This can be a benefit for all parties, depending on the circumstances. It’s particularly helpful when it comes to stamp duty. If you think you want a mortgage like this, it’s always worth checking with a solicitor or a tax advisor to understand the potential stamp duty liabilities first.
What responsibilities do the joint borrower and sole proprietor have in a JBSP mortgage?
Jon: They are both jointly liable for the mortgage payments. It’s up to you how you decide who pays what, but ultimately the mortgage payments will need to be paid.
The joint borrower will be required to obtain independent legal advice from a solicitor before the completion of the mortgage. This is key, so they have a full understanding of their responsibilities.
Can I get a JBSP mortgage as a first-time buyer?
Adam: You can. JBSP is available for many situations, whether that be your first purchase, moving home, a remortgage, and, in some circumstances, even buying an investment Buy to Let property.
Most lenders typically offer this type of mortgage to help people get on the property ladder. But there are lenders to help with other situations, as well, such as a divorce or a separation.
You might be trying to buy out your ex-partner but you can’t afford the mortgage by yourself. You may seek help from family or friends to go on the mortgage with you.
What criteria do you need to meet for a JBSP mortgage?
Jon: There are no real differences. We need ID, proof of address, income evidence and bank statements for both parties – the joint borrower and the sole proprietor.
One of the key considerations with some lenders is the age of the joint borrower, rather than the owner. This can affect the borrowing potential, because their income could change depending on when they will be nearing retirement. But most lenders understand that JBSP is a short-term solution.
We do need an understanding of your future plans – how will the sole proprietor eventually take on the mortgage themselves? Do you have a clear career path, with salary increases along the way?
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Do JBSP mortgages require a larger deposit compared to standard mortgages?
Adam: No, not necessarily. With most lenders, they don’t, but you should always be aiming for a minimum of 5% of the purchase price.
The bigger the deposit you have, the more options you’ll have and the more lenders will be available. Also, a larger deposit usually means lower interest rates.
Do you pay stamp duty on a JBSP mortgage?
Jon: Stamp duty is a potential liability when you’re buying a property, and a key reason why you may choose a JBSP is due to stamp duty considerations.
Stamp duty liability is usually based on the sole proprietor’s home ownership status, as opposed to the joint borrower’s. This is a vital consideration when the additional borrower already owns a property in the background.
Can you have a sole mortgage on a joint property?
Adam: As of today in October 2025, this isn’t possible. I am aware that historically a few lenders did consider this arrangement, but it’s not available anymore.
What’s the difference between a joint mortgage and a JBSP mortgage?
Jon: With a joint mortgage, you’re both named on the mortgage and jointly named on the title of the property. Meanwhile, on a Joint Borrower Sole Proprietor mortgage, you’re jointly on the mortgage, but there’s only one party on the title of the property.
What’s the difference between a guarantor mortgage and a JBSP mortgage?
Adam: JBSP is essentially the modern equivalent of a guarantor mortgage. It’s a mortgage where additional borrowers share the responsibility of paying the mortgage, in order to boost how much you can borrow.
What are the pros and cons of JBSP mortgages?
Jon: The key benefit is giving somebody the ability to obtain a mortgage who can’t afford to do it by themselves. They use the other person’s income to make a property they want to buy affordable.
There’s also the stamp duty consideration. The main borrower won’t lose their first-time buyer status for stamp duty purposes because of the joint borrower owning another property.
A drawback for the joint borrower is that the mortgage liability could affect them in the future. It could affect an affordability assessment for other borrowing. Another key factor is that if both parties stop paying the mortgage, it affects the credit file for both of them.
Is there anything else we need to know about JBSP mortgages?
Adam: It’s important to get the correct professional advice from all parties for the transaction.
That’s advice from a mortgage broker to find a suitable lender; advice from a solicitor about the pros and cons regarding the ownership of the property, and also tax advice to make sure your intentions are correct.
This is a big commitment, so everyone involved needs to be comfortable with what they’re getting into.
Key Takeways:
- A Joint Borrower Sole Proprietor (JBSP) mortgage allows a family member or friend to join the mortgage to help with borrowing capacity without having ownership of the property.
- Both the joint borrower and sole proprietor are jointly liable for mortgage payments, and the joint borrower must obtain independent legal advice.
- JBSP mortgages are available for various situations, including first-time buyers, moving home, remortgaging, and even some Buy to Let properties.
- Criteria for a JBSP mortgage are similar to standard mortgages, requiring ID, proof of address, income evidence, and bank statements for both parties. The age of the joint borrower is a key consideration for some lenders.
- Stamp duty liability is typically based on the sole proprietor’s home ownership status, which can be a significant benefit for JBSP mortgages, especially if the joint borrower already owns another property.
YOUR HOME MAY BE REPOSSESSED IF YOU DO NOT KEEP UP WITH YOUR MORTGAGE REPAYMENTS.
For specialist tax advice, please refer to an accountant or tax specialist.