What is a guarantor mortgage?

A mortgage where someone else, usually a parent, agrees to be liable for payments if the borrower can't pay. The guarantor doesn't own the property and doesn't make monthly payments, but if the borrower defaults, the lender can pursue the guarantor for the missed amounts.

Who can be a guarantor on a mortgage?

Most lenders restrict guarantors to immediate family (usually parents, sometimes grandparents or siblings). They need stable income, must pass credit checks, and must take independent legal advice. Typically lenders want the mortgage to end before the guarantor reaches 80-85.

Is JBSP better than a guarantor mortgage?

Usually yes. JBSP avoids the Stamp Duty second-home surcharge for the parent (because the parent isn't on the deeds), is accepted by more mainstream lenders, and has a cleaner exit when the borrower can afford the mortgage solo.

What's the risk to a guarantor?

If the borrower defaults, the guarantor is liable for the missed payments. Their credit file gets damaged, their own property may be at risk if it's been charged as security, and cash savings held as collateral may be locked up. They also have reduced borrowing capacity for themselves while the guarantee is in place.

Can a guarantor be removed later?

Usually yes, by remortgaging. Once the borrower can pass affordability on their own, a remortgage to a new lender removes the original guarantor liability. The process is the same as any standard remortgage.

Does a guarantor have to pay Stamp Duty?

No. Because the guarantor doesn't own the property, they don't pay SDLT and the second-home surcharge doesn't apply to them. This is one of the key differences from arrangements where the parent goes on the deeds.

Guarantor Mortgages Explained (UK)

A guarantor mortgage is one where someone else, usually a parent, agrees to be liable for the loan if you can't pay. They don't own any part of the property, they don't pay anything monthly while you keep up the payments, but if you default, the lender can pursue them for the missed amounts. Once a common path for first-time buyers, guarantor mortgages have been largely overtaken by newer products like JBSP, but they're still worth understanding.

How a guarantor mortgage works

The structure is simple: you take out the mortgage as normal, but a guarantor signs a separate document promising to cover any missed payments. The guarantor's name doesn't appear on the property deeds and they don't pay tax as if they owned a second property. The lender uses their income and credit history to bolster the affordability assessment, allowing you to borrow more than your income would normally support.

Often the guarantor needs to either deposit savings with the lender as collateral, or have their own property charged as security. The exact mechanics depend on which product you pick.

Who can be a guarantor

Most lenders restrict guarantors to immediate family, typically parents, sometimes grandparents or siblings. They'll require the guarantor to:

Have stable, demonstrable income to support the additional liability.
Pass independent credit checks.
Take independent legal advice before signing.
Usually be under 75 at the start, with the mortgage term ending before they reach 80-85.

The risks for the guarantor

Guarantor mortgages put the guarantor in a serious position:

Their credit file is on the hook. Missed payments by the borrower mark the guarantor's file too.
Their own property could be at risk if they've offered it as security.
Their cash savings could be locked up for years if they're held as collateral.
Family relationships strain. If the borrower falls behind, the parent is suddenly on the hook financially, a recipe for resentment.
The guarantor's own future borrowing is limited. Lenders treat them as having that liability, reducing what they can borrow for themselves.

Why JBSP often beats guarantor

Joint Borrower Sole Proprietor (JBSP) mortgages have largely replaced guarantor mortgages in the UK. Under JBSP, the parent is jointly on the mortgage but NOT on the property deeds, they're liable for payments alongside the buyer, but the property isn't theirs.

Why JBSP usually wins:

No Stamp Duty surcharge for the parent. Because they're not on the deeds, the second-home SDLT surcharge doesn't apply to them.
Clean exit. Once the borrower can afford the mortgage on their own, the parent can be removed via remortgage. With a guarantor mortgage, exit is similar but procedurally different.
Lenders are more comfortable. JBSP is widely accepted by mainstream lenders; guarantor mortgages have become specialist.

Other modern alternatives

Beyond JBSP, consider:

Freedom to Buy (the permanent 5% deposit Mortgage Guarantee Scheme), sometimes the buyer can borrow enough on their own with just a 5% deposit and government guarantee in the background.
Family Springboard mortgages (Barclays' product) and similar, parents deposit savings with the lender for 5 years; in return, the child gets a 100% LTV mortgage and the parent's deposit earns interest. After 5 years, the deposit comes back.
Gifted deposit, parents simply give the child the deposit cash. Cleanest option if the family has the savings to spare.
Loan from family, formally documented, repaid over time. May affect the buyer's affordability assessment.

When a guarantor mortgage still makes sense

Narrow set of cases:

The buyer has decent income but a thin or recently-rebuilt credit file.
The buyer is self-employed with insufficient accounts history for mainstream lenders.
The buyer's affordability is just barely failing on their own, a guarantor's income tips it over.
The family wants to ring-fence which assets are 'on the line', guarantor structures are sometimes cleaner for that than JBSP.

Independent legal advice, non-negotiable

Every lender requires guarantors to take independent legal advice before signing. This isn't a formality, the solicitor's job is to make sure the guarantor genuinely understands the consequences. The buyer and the guarantor cannot use the same solicitor, and many lenders require the advice to be documented in a specific way.

Budget £200-£500 for the guarantor's independent legal advice, on top of normal conveyancing.

If you're considering family help to get on the ladder, talk through the options properly before defaulting to 'guarantor mortgage'. JBSP, Springboard products, gifted deposits and Freedom to Buy can all do similar jobs with less risk. Debbie at DS Financial walks families through which structure fits their situation cleanest.

General information, not financial advice. Your home may be repossessed if you do not keep up repayments on your mortgage.

Sources: MoneyHelper, Joint mortgages and family help, FCA, Mortgages, UK Finance, Mortgage industry data.

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Guarantor Mortgages Explained