Buying a UK property with a partner you’re not married to, a sibling, a close friend, or another unrelated co-buyer is entirely possible, but it lacks some of the automatic legal protections marriage provides – worth understanding and planning for properly rather than assuming the same rules apply.
Why Unmarried Co-Buyers Don’t Get the Same Automatic Protections as Spouses
Married couples benefit from specific legal frameworks around property and finances that simply don’t apply to unmarried co-buyers, regardless of how long you’ve been together or how the relationship is structured. This makes explicit agreements between unmarried co-buyers considerably more important than they would be for a married couple.
A Cohabitation or Co-Ownership Agreement, Separate From the Mortgage Itself
Beyond the mortgage application, it’s genuinely worth having a solicitor draft a formal agreement covering how you’ll handle the property if the relationship ends, how ongoing costs are split, what happens if one party wants to sell and the other doesn’t, and how any unequal financial contributions are reflected in ownership. This is a legal document outside the mortgage broker’s remit, but it’s directly relevant to protecting both parties.
How Lenders Assess an Unmarried Joint Application
Practically, most lenders assess joint applications from unmarried co-buyers in much the same way as married couples – combined income, combined credit history, combined affordability. The relationship status itself isn’t typically the deciding factor; what matters is whether both applicants meet the lender’s normal criteria together.
Unequal Deposit Contributions Between Unmarried Buyers
If one buyer is contributing a significantly larger deposit, this is exactly the kind of situation where tenants in common ownership (reflecting the actual unequal contribution in defined shares) tends to make more sense than joint tenancy, which assumes equal ownership regardless of who put in what.
What Happens if the Relationship Ends
Without married couples’ legal frameworks to fall back on, unmarried co-owners are more reliant on whatever agreement they put in place at the outset (or, absent one, general property law principles that can be more complicated and costly to resolve through the courts). This is precisely why the upfront agreement matters more here than for married buyers.
Buying With a Sibling or Close Friend as an Investment, Not a Home
If the purchase is genuinely an investment rather than a home you’ll live in together, tenants in common with clearly documented shares, plus a formal agreement covering decision-making and exit routes, is generally the more appropriate structure than assuming an informal understanding will hold up if disagreements arise later.
If One Party Wants to Raise Funds Against the Property Later
If one co-owner wants to release equity for their own purposes while the other doesn’t, this needs everyone’s agreement, since all owners typically need to consent to a mortgage or remortgage decision affecting jointly owned property. Our Second Charge Mortgages page covers an alternative that’s sometimes more achievable than a full remortgage in this kind of situation, though it still requires all owners’ agreement.
If This Is a First Purchase for Either of You
Our First-Time Buyer Expat Mortgages page covers the additional first-purchase considerations relevant if either co-buyer hasn’t owned UK property before, on top of the unmarried co-ownership considerations covered here.
Remortgaging as Unmarried Co-Owners
The same “all owners must agree” principle applies to remortgaging a jointly owned property – our Expat Residential Remortgage page covers what that process generally involves, which is relevant regardless of your relationship status to your co-owner.
Frequently Asked Questions
Do lenders treat unmarried joint applicants differently to married couples?
Generally not in terms of the mortgage assessment itself – combined income and affordability are assessed similarly regardless of relationship status.
Do we need a formal agreement beyond the mortgage paperwork?
Strongly advisable – a cohabitation or co-ownership agreement covering contributions, decision-making, and exit routes protects both parties in ways the mortgage documents alone don’t.
What happens if we split up and disagree about selling?
Without a prior agreement, this can become genuinely complicated and costly to resolve – exactly why having one in place from the outset matters.
Can we reflect unequal deposit contributions in our ownership shares?
Yes, through tenants in common ownership with defined shares, rather than joint tenancy’s assumed equal split.
Get in touch with details of your joint purchase plans, and we’ll help with the mortgage side while strongly recommending proper legal advice on the ownership agreement itself.
