Joint Borrower Sole Proprietor Mortgage Guide

Looking to get on the property ladder, but aren’t quite meeting Lenders Criteria? A Joint Borrower Sole Proprietor Mortgage could be the right choice for you.

Whilst these Mortgages are quite different to Guarantor Mortgages, they have in many Lenders cases replaced them.

In this guide we’ll go through everything you need to know, to set you up nicely for when you come to apply or speak to a Mortgage Advisor.

What is a Joint Borrower Sole Proprietor mortgage?

How does a Joint Borrower Sole Proprietor mortgage work?

What’s the difference between a Joint Borrower Sole Proprietor and a Joint Mortgage?

Are Joint Borrower Sole Proprietor Mortgages the same as Guarantor Mortgages?

Pros and cons of Joint Borrower Sole Proprietor Mortgages – complete in a table

Can I have a Joint Borrower Sole Proprietor Mortgage with my Partner?

Minimum deposit required for a Joint Borrower Sole Proprietor Mortgage?

What criteria will my Guarantor have to meet?

When could I remove my Guarantor from the Mortgage?

My Guarantor is on a Mortgage of their own, how will this affect the Mortgage?

The Top 10 Lenders which Offer Joint borrower sole proprietor mortgage?

How does Stamp Duty work for Joint Borrower Sole Proprietor Mortgages?

What is a Joint Borrower Sole Proprietor Mortgage?

A Joint Borrower Sole Proprietor Mortgage is a specialist mortgage product where multiple people are listed as borrowers, but only one person is the legal owner of the property.

This can improve the main buyer’s affordability assessment by including the income of a parent, partner or other family member without giving them ownership rights.

This is particularly useful for:

First time buyers who have limited income.

Parents with assessable income that want to help their children buy property.

Borrowers struggling with overall affordability.

Importantly, only the Sole Proprietor (the person living in and owning the property) is responsible for the property in legal terms — for things like Stamp Duty, ownership rights and future sale proceeds.

How does a Joint Borrower Sole Proprietor Mortgage work?

It all comes down to risk. And while some Mortgage Lenders put in place strict criteria which can penalise self employed applicants, others create criteria to specifically help them.

For example, some Lenders will take your most recent tax years earnings to give a boost to borrowing capacity. While others will always take an average of the last two years earnings or the latest years (only if it’s lower).

Some will require you to be in business for 2 years, and others only a year (or less in some cases such as CIS Contractors).

What is the difference between a Joint Borrower Sole Proprietor Mortgage and a Joint Mortgage?

Feature	JBSP Mortgage	Joint Mortgage
Ownership	One borrower (sole proprietor) owns the property	All borrowers own the property jointly
Stamp Duty	Only the sole proprietor is liable	All buyers liable – may incur higher rates if one already owns property
Use of income	Multiple incomes considered for affordability	Same
Guarantor role	Active borrower, not just a backup	All borrowers are owners

The Joint Borrower Sole Proprietor route tends to be the most tax advantageous route for the additional borrower/Guarantor.

Are Joint Borrower Sole Proprietor Mortgages the same as Guarantor Mortgages?

Whilst both of these type of Mortgages are similar, they are still distinctly different.

Although for the purposes of this guide, we will on occasion still refer to the additional borrower as a Guarantor.

Aspect	JBSP Mortgage	Guarantor Mortgage
Involvement	Supporter is a co-borrower on the loan	Guarantor only steps in if repayments fail
Affordability	All incomes assessed	Primarily the buyer’s income, with backup from guarantor
Legal risk	Shared responsibility	Guarantor only becomes liable under specific conditions
Ownership	Sole buyer owns the home	Sole buyer owns the home

Pros and Cons of a Joint Borrower Sole Proprietor Mortgage?

Pros	Cons
Boosts borrowing power – Multiple incomes considered can increase your borrowing capacity.	All borrowers are financially liable – Even if not living in the property.
Avoids Stamp Duty surcharge – If co-borrower owns another property, they don’t pay the 3% surcharge.	Legal complexities – May require legal advice and declarations for transparency.
Helps first time buyers – Especially when income alone wouldn’t meet affordability requirements.	Can complicate Remortgaging – In future, all borrowers may need to be reassessed.
Ownership stays with the main borrower – Keeps ownership simple, especially for inheritance planning.	Guarantor’s own affordability affected – Their ability to borrow elsewhere can be limited.

Can I have a Joint Borrower Sole Proprietor Mortgage with my partner?

Yes, but it depends on your long-term plans and you’ll need to carefully consider doing this, ideally with a Solicitor so you both fully understand the implications of proceeding on this basis.

There are lots of different variables both parties will need to consider with a Solicitor, such as:

Are the applicants Married.

Who will be contributing toward the deposit.

Who will be contributing toward the Mortgage.

Most couples will opt for a joint mortgage, but a JBSP could work if one partner has bad credit or already owns another property.

Minimum deposit required for a Joint Borrower Sole Proprietor Mortgage?

This varies from Lender to Lender, but typically it will be the same as it would be for a standard Residential Mortgage, typically 5%:

Meaning a £200,000 Purchase would equal a deposit of £10,000.

Some Lenders do require a larger deposit than this, and to achieve a Purchase with a 5% deposit you will typically need a squeaky clean credit history.

What Criteria will my Guarantor have to meet?

Simply put, your Guarantor will still have to meet the same criteria that you do. Standard Criteria such as:

Age: Most Lenders will require your Guarantor to be under the age of 70-80 by the end of the overall Mortgage term. This often is the greatest issue see popping up with JBSP Mortgages.

Credit Criteria: Will usually require a clean credit history. With one or two Lenders considering Adverse Credit, usually subject to minimum deposit of 15%.

Income: Will need to have assessable income for the whole term, if the Mortgage extends into retirement, then retirement income will likely be needed by the Lender.

Existing Debt: Existing large debts such as other Mortgages, can also typically create an issue with affordability.

When can I remove my Guarantor from the Mortgage?

You can usually remove your Guarantor when your income or financial situation improves enough so you can support the mortgage on your own.

You can remove the Guarantor by completing a Remortgage to a new Mortgage Lender.

Or by contacting your existing Lender and seeing if you meet their criteria to support the Mortgage on your own.

My Guarantor is on a Mortgage of their own – how will this affect things?

If your other borrower is already on a Residential Mortgage of their own, it will mean their Mortgage Capacity will be reduced as a result.

Buy to Let Mortgages are less of an issue, as they are deemed as self financing by most Mortgage Lenders.

Your Advisor or Lender will take additional Mortgages into account when completing their affordability assessments.

The Best 10 Mortgage Lenders which off Joint Borrower Sole Proprietor Mortgages

1. Barclays – Known for flexible JBSP mortgages, especially for first time buyers with family support.

2. Metro Bank – Offers up to four applicants with just one proprietor, ideal for complex income setups.

3. Nationwide – Supports JBSP on selected products, though stricter on age and term limits.

4. Halifax – Offers JBSP options on their first time buyer ranges with competitive rates.

5. Santander – Allows JBSP but requires strong documentation and often a larger deposit.

6. Family Building Society – Focuses on family-backed mortgages, ideal for parent-child scenarios.

7. Skipton Building Society – Offers JBSP with a focus on intergenerational borrowing.

8. Clydesdale Bank (Virgin Money) – Known for flexibility on JBSP products and underwriting.

9. Leeds Building Society – Offers JBSP with detailed affordability models and online applications.

10. Vida – a Specialist Mortgage Lender who has a wide array of JBSP products to support applicants who have adverse credit.

Each lender has unique criteria — we can put you in touch with Mortgage Advisor which specialises in this area.

How does Stamp Duty work for Joint Borrower Sole Proprietor Mortgages?

One of the key benefits of JBSP mortgages is how Stamp Duty is calculated.

Only the sole proprietor (legal owner) is considered for Stamp Duty purposes.

So if they are a first time buyer, they can benefit from Stamp Duty relief.

This can result in significant savings, especially in family backed purchases.

Need Advice? Speak to one of our Mortgage Advisors

A Joint Borrower Sole Proprietor mortgage can be a great way to overcome affordability problems and get on the property ladder.

But with legal implications and only a small list of Lenders which deal with these Mortgages, it’s important to get independent advice.

Get in touch with us via our contact form if you would like support in finding a Specialist Mortgage Advisor to guide you through the process.