Joint Borrower Sole Proprietor mortgages

More parents are helping their adult children onto the property ladder with JBSP

At Trinity Financial, we understand how challenging it is for many young adults to get onto the property ladder today. That’s where a Joint Borrower, Sole Proprietor (JBSP) mortgage can make a real difference — an innovative, flexible way for parents (or other family members) to support without giving up ownership of the home.

The idea is for parents to be able to use their income to boost their adult children's mortgage borrowing capacity, without incurring the higher rate of stamp duty, if they already own a property. In some cases, adult children also help their parents obtain mortgages to move home or remortgage using JBSP. 

What is a JBSP mortgage?

A JBSP mortgage typically allows up to four borrowers (from different households) to combine incomes and meet affordability criteria, but legally only one person is the property owner (the “sole proprietor”). 

• All borrowers are jointly and severally liable for the repayments — so if the mortgage falls into arrears, any borrower can be held fully responsible.

• Only the named sole proprietor is listed on the title deeds and is the owner of the property. The supporting borrower(s) (for example a parent) help via income and liability, but do not have legal ownership rights.

Why are they so popular?

• Property prices continue to rise in many areas, and affordability is stretched. A JBSP mortgage allows families to pool their incomes to increase the amount that can be borrowed. 

• They provide an alternative to pure guarantor mortgages: rather than simply guaranteeing the loan, the extra borrower’s income is included in affordability calculations. 

• For parents, this type of arrangement means you can support your child’s first-home purchase without being named on the deeds — you help them onto the ladder, and remain free of ownership complications. 

• Since the owner is the younger buyer, there are tax benefits: the supporting borrower normally avoids liability for stamp duty surcharges when they already own a property. Mortgage lenders insist that legal advice is taken so all parties fully understand their liabilities. 

Who uses JBSP mortgages?

First-time buyers

Young professionals whose income alone may not support the size of the mortgage needed. A parent adds their income; the young adult becomes the sole proprietor.

Children of older owners

Older homeowners or parents may want to assist their children become homeowners but prefer not to take on joint ownership. 

Family members supporting each other

It’s not just parents and children — siblings, grandparents or legal guardians may also be involved (depending on lender criteria). 

How can parents help via a JBSP mortgage?

1. Add your income — as a supporting borrower, you add your income to the application, which helps with affordability calculations and enables a larger loan for your adult child. 

2. Remain outside ownership — you won’t be on the title deeds. Your child will be the legal owner, controlling the property, decisions and future sale.

3. Become jointly liable — though you do not own the home, you agree to be responsible for repayments. If your child cannot meet the cost, you (and any other borrower) are liable.

4. Plan for the future exit — when your child’s income increases sufficiently, many lenders allow you to be removed from the mortgage and the mortgage transferred into the child’s sole name. 

5. Preserve rights and tax position — because you are not an owner, you should avoid extra tax burdens such as the second-home surcharge for Stamp Duty, and are relieved of ownership risks.