Boost how much you can borrow
Joint Borrower Sole Proprietor mortgages
Can't borrow quite enough for the house you want? Your family could give your affordability an extra boost.
You could borrow more than you think with a 'Joint Borrower Sole Proprietor' (JSBP) mortgage. JBSP mortgages can be helpful for first time buyers who are buying alone, or are on a lower income.
How a Principality JBSP mortgage works
A family member’s name is added to your mortgage application. We can then take their income into account when working out how much you can borrow.
By doing this your family member agrees to pay your repayments if you can’t meet them (a bit like a guarantor mortgage). But unlike a guarantor mortgage, they aren't offering their own property or savings up as security against your loan.
Your family member won't own any part of the home you’re buying; it’s completely in your name. And they won't need to pay Stamp Duty or Land Transaction Tax
Are there any risks for the family member(s) helping you?
Your family member(s) should take independent legal advice and talk everything through with a mortgage advisor. Their solicitor should make sure they understand any risks of being named on your mortgage. Some key things to be aware of are:
- You pay the mortgage repayments - But if you can’t, your family member(s) agrees to do so for you. If nobody makes the repayments, it affects the credit of everyone on the mortgage.
- The home belongs to you - As they don’t own the home, they can’t force you to sell it.
- We take their affordability into account to boost how much you can borrow - This means they may not be able to borrow more on a mortgage themselves while they are on yours.
The important stuff
No; you can remove them when you’re ready. Your financial circumstances may change in the future. If your salary goes up, or once you've paid off a significant part of the mortgage you may feel ready to fully take on the mortgage yourself. A JBSP mortgage is a temporary affordability boost to get you on the ladder.
Family help comes in all shapes and sizes. You can get help with your mortgage affordability from: your spouse, grandparent, parent, sibling, or a legal guardian. Children and grandchildren can also help their parents or grandparents to buy.
The home will legally belong to you alone. You’ve borrowed together (joint borrowers) but you’re the only owner (the sole proprietor).
You're responsible for making sure you make your monthly mortgage repayments. We'll assess this together as part of your application. It's part of the usual affordability checks we carry out.
Our Joint Borrower Sole Proprietor mortgages
|Initial rate||Until||Then our standard variable rate, less a discount of 0.50%||Until||Then standard variable rate||Overall cost for comparison (APRC)||Product Fee||Cashback|
|90% LTV Fixed Rate JBSP Mortgage||6.00%||28/02/2026||7.10%||28/02/2029||7.60%||7.4%||£0||There is no cashback facility with this product.||More details|
|90% LTV Fixed Rate JBSP Mortgage||5.70%||28/02/2029||N/A||N/A||7.60%||7.0%||£0||There is no cashback facility with this product.||More details|
Ways to start your application
Our contact centre is open 9am to 5pm Monday to Friday and 9am to 1pm on Saturday and our branches are located across Wales and the borders, find a branch.
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