A joint borrower sole proprietor (JBSP) mortgage helped a Sleaford first-time buyer borrow more using a parent’s income

Spolton Mortgages arranged a joint borrower sole proprietor (JBSP) mortgage for a first-time buyer in Sleaford, using a parent’s income to bridge an affordability gap.

The situation. A young first-time buyer in Sleaford came to us with a 5% deposit saved and a clear budget. The monthly payments on the home they wanted were comfortably affordable. The problem was on paper: on a 95% mortgage, the lender’s income multiplier did not stretch far enough to reach the loan they needed. The affordability was there in real life, just not in the lender’s calculation.

The assumption. When we talked it through, the client’s parents were happy to help. As they put it, Dad would “act as guarantor”. That is the phrase most people reach for, but a traditional guarantor mortgage is rarely the best route now, and few lenders still offer one.

The solution: joint borrower, sole proprietor. John looked at the options and structured the purchase as a joint borrower sole proprietor (JBSP) mortgage. The first-time buyer buys the property in their sole name and is the only owner on the title deeds. Dad joins the mortgage application as a joint borrower, so his income and outgoings are added to the affordability assessment. That extra income closed the gap, without Dad going on the deeds.

Why that matters. Because the buyer stays the sole legal owner, JBSP keeps them in the driving seat and, in most cases, protects their first-time buyer stamp duty position, which we check for every client. That is the practical difference between a guarantor arrangement and JBSP: with JBSP the family member is a full joint borrower whose income actually counts towards the loan, rather than simply standing behind it.

The outcome. John packaged the case, the application went in, and a mortgage offer was issued within 10 days. The client is now waiting on the legal work to complete before they collect the keys to their first home.

Who this helps. JBSP suits first-time buyers whose payments are affordable but whose income multiplier falls just short, and who have a parent or family member willing to support the borrowing. Every case is different, so it is worth talking through your own numbers.

If you are buying your first home and the figures are close but not quite there, talk to a first-time buyer adviser.

Your home may be repossessed if you do not keep up repayments on your mortgage.