A guarantor mortgage helps people who cannot meet standard mortgage criteria — whether due to a small deposit, low income, or limited credit history — by allowing a family member to provide additional security. This guide explains how they work, the different types, and the significant responsibilities involved.
How Guarantor Mortgages Work
A guarantor provides a safety net for the lender. If you fail to meet your mortgage payments, the lender can turn to your guarantor to cover them. In return, the lender is willing to offer you a mortgage that you might not qualify for on your own.
The guarantor does not own any share of the property and their name is not on the title deeds. They are providing a guarantee, not buying jointly.
Types of Guarantor Mortgage
Savings-Based Guarantor
The guarantor deposits a sum of money (typically 10–20% of the property value) into a savings account held by the lender. This money is locked away as security for a set period.
| Feature | Detail |
|---|---|
| Guarantor provides | Cash savings (10–20% of property) |
| Savings locked for | 3–5 years (or until LTV reaches target) |
| Interest earned | Some schemes pay interest on locked savings |
| Risk to guarantor | Could lose savings if borrower defaults |
Property-Based Guarantor
The lender places a legal charge against the guarantor’s own property as security. This is the most serious type of guarantee.
| Feature | Detail |
|---|---|
| Guarantor provides | Legal charge on their home |
| Charge remains for | Duration of guarantee period |
| Risk to guarantor | Property could be at risk if borrower defaults |
| How it helps | Allows borrower to get 100% LTV or close to it |
Income-Based Guarantor
The guarantor’s income is used alongside yours to meet the lender’s affordability criteria. Their income boosts the total assessed income, increasing how much you can borrow.
Who Needs a Guarantor Mortgage?
Guarantor mortgages are most useful for:
- First-time buyers with no deposit — some guarantor products allow 100% LTV
- Buyers with a small deposit — accessing better rates normally reserved for lower LTV brackets
- Young professionals — who earn a good salary but have not yet saved enough for a deposit
- Those with limited credit history — recent graduates or people new to the UK
The Financial Impact on the Guarantor
Being a guarantor has significant financial implications:
Credit Commitments
The guarantee shows on the guarantor’s credit file as a contingent liability. This may:
- Reduce the guarantor’s ability to borrow (e.g. for their own remortgage or other loans)
- Affect their credit score
- Be visible to other lenders
Worst-Case Scenario
If the borrower defaults and the guarantor cannot cover the payments:
- Savings-based: The lender takes the locked savings
- Property-based: The lender could ultimately seek possession of the guarantor’s property
- Both parties: Credit files are damaged, legal action may follow
This is why independent legal advice for the guarantor is essential before entering any guarantee arrangement.
Alternatives to Guarantor Mortgages
Before committing to a guarantor arrangement, consider these alternatives:
| Option | How It Works | Avoids Guarantor Risk? |
|---|---|---|
| Gifted deposit | Family gifts money for the deposit — no repayment expected | Yes |
| Family offset mortgage | Family links savings to borrower’s mortgage to reduce interest | Yes — savings remain family’s own |
| Joint mortgage | Buy together with the family member | No — both parties liable |
| Shared ownership | Buy a share with a smaller deposit | Yes |
| Lifetime ISA | Government adds 25% to your deposit savings | Yes — but takes time to build |
| Longer saving period | Wait and build a larger deposit independently | Yes |
A gifted deposit is often the simplest and least risky way for family to help. The family member gives (not lends) money for the deposit, confirmed by a signed gifted deposit letter. They take on no ongoing liability and their credit is unaffected.
Choosing a Guarantor Mortgage
If a guarantor mortgage is the right route for you:
- Speak to a mortgage broker — they know which lenders offer guarantor products and can match your circumstances
- Ensure the guarantor gets independent legal advice — this is mandatory with some lenders and essential regardless
- Check the guarantee duration — prefer products where the guarantee drops off after a set period or when a target LTV is reached
- Have an honest conversation — discuss worst-case scenarios openly with your guarantor
- Check the guarantor’s own finances — ensure they can genuinely afford the risk without jeopardising their own financial security
- Consider insurance — life insurance and income protection for the borrower can protect the guarantor against the most serious risks
Key Takeaway
A guarantor mortgage can be a valuable bridge to homeownership, but the guarantor is taking on real financial risk. Both parties must go in with full understanding of the obligations, proper legal advice, and an honest assessment of affordability. If the risk feels uncomfortable for either party, explore the alternative routes listed above — several can achieve a similar outcome with less exposure.