Pooling resources with friends to buy property sounds like a neat workaround to a brutal housing market — and in many cases it genuinely is. But co-buying with friends is not simply “splitting the cost.” It is a legally complex arrangement that can destroy friendships, wreck credit files, and trigger unexpected tax bills if you get it wrong. Before you start browsing Rightmove together, you need to understand exactly what you are signing up for.
Joint and Several Liability: The Fact Most Co-Buyers Get Fatally Wrong
Here is the single most important thing to understand: on a joint mortgage, the lender can pursue either borrower for 100% of the outstanding debt — not just their “share.” If your friend loses their job, moves abroad, or simply stops paying, the mortgage company will not chase them proportionally. They will come to whoever is easiest to collect from, and that person owes the lot.
This is not a theoretical risk. It plays out in county courts every week. Your co-buyer’s financial stability is not a background detail — it is as central to your decision as the property itself. If they have a shaky employment history, a spending habit they minimise, or plans to change career in two years, you need to factor that in with clear eyes, not hopeful ones.
Your Future Borrowing Capacity Takes a Direct Hit
What most articles skip entirely is the impact on your ability to borrow in the future. When you apply for a mortgage down the line — say you want to buy a place with a partner — lenders will stress-test you against the full outstanding balance of the joint mortgage, not your notional half. If £200,000 remains on the joint loan, your affordability assessment carries that entire figure as a committed obligation.
For many co-buyers in their late twenties or early thirties, this is the hidden cost that bites hardest. The very strategy you used to get onto the ladder can lock you out of the next step for years. Plan your exit timeline before you enter, not after you feel stuck.
Tenancy in Common: The Only Sensible Ownership Structure
There are two ways to hold property jointly in England and Wales: joint tenancy and tenancy in common. Joint tenancy includes the right of survivorship — if one owner dies, their share passes automatically to the survivor, regardless of their will. That may suit married couples; it is almost never appropriate for friends.
Tenancy in common allows you to hold the property in unequal shares (reflecting actual contributions), leave your share to whoever you choose, and keep your interest legally distinct. If you contributed 65% of the deposit and your friend contributed 35%, a tenancy in common lets you formalise that. Under joint tenancy, you would each be treated as owning 50% — a gift to your friend’s estate and a potential headache with HMRC.
The Declaration of Trust: Non-Negotiable Documentation
A Declaration of Trust (sometimes called a Deed of Trust) is the document that records each party’s beneficial interest, what happens on sale, how unequal contributions are treated, and whether additional payments count as loans or equity adjustments. Without one, courts and HMRC will default to equal shares regardless of who actually put in what.
This is not optional paperwork. It is the legal foundation of your arrangement. Critically, it should be executed as a deed, not a simple contract. A deed carries a 12-year limitation period for enforcement, compared with six years for a standard contract. Given that co-ownership disputes often surface years after purchase — when someone wants to sell, marry, or relocate — those extra six years of enforceability matter enormously.
Your Declaration of Trust should address, at minimum:
- Each party’s percentage share and how it was calculated
- Whether unequal contributions are treated as a loan (repayable with or without interest) or an outright equity adjustment
- A right of first refusal if either party wants to sell their share
- A buy-sell mechanism with an agreed valuation method (independent RICS surveyor, average of two valuations, etc.)
- An exit timeline — maximum notice period and a forced-sale backstop
- A shared expense account for mortgage payments, insurance, service charges, and maintenance
- Occupancy rules, including whether partners or lodgers can move in and on what terms
- Renovation and improvement consent thresholds — what spend requires unanimous agreement
TOLATA 1996: The Nuclear Option Nobody Warns You About
Under the Trusts of Land and Appointment of Trustees Act 1996, either co-owner can apply to the court to force a sale of the property, even if the other party refuses. The court considers factors including the purpose for which the property was bought, the welfare of any children in occupation, and the interests of secured creditors — but in practice, where there is no ongoing purpose and one party wants out, a sale is usually ordered.
TOLATA applications are expensive, adversarial, and friendship-ending. The single best way to avoid one is to have a robust co-ownership agreement with a clear exit mechanism already in place. Think of it as a pre-nuptial agreement for your property partnership.
The SDLT Surcharge Trap
This catches people every year. If either co-buyer already owns residential property anywhere in the world — even a buy-to-let flat, even an inherited cottage in rural France — the 3% Stamp Duty Land Tax higher rate applies to the entire purchase price. It does not matter that the other buyer is a first-time buyer. It does not matter that the existing property belongs solely to one of you. The surcharge applies to the whole transaction.
On a £400,000 purchase, that is an additional £12,000 in tax. This needs to be discussed and allocated before you make an offer, not discovered at the eleventh hour by your conveyancer.
Tax Realities: CGT and Inheritance Tax
Principal Private Residence Relief shelters you from Capital Gains Tax on the sale of your main home — but only for the period during which it was genuinely your main residence and only on the share you own. If one co-buyer moves out and the property ceases to be their principal residence, their share starts accruing a potential CGT liability from that point. The current annual exempt amount is modest, and higher-rate taxpayers face a 24% CGT charge on residential property gains.
On Inheritance Tax, your share of the property forms part of your estate. If shares were gifted or transferred below market value — perhaps as part of an informal arrangement between friends — HMRC can treat that as a potentially exempt transfer with a seven-year clock. Get proper tax advice before structuring anything creative.
What to Do Next
If you are seriously considering buying with a friend, take these steps in order. First, each of you should obtain an independent Agreement in Principle from a mortgage broker to understand your individual and combined borrowing capacity — and the impact on future applications. Second, instruct a solicitor experienced in co-ownership to draft a Declaration of Trust executed as a deed. Do not use a generic template. Third, agree your co-ownership terms in writing before you start viewing properties — when goodwill is highest and stakes are lowest. Finally, review the arrangement annually. Circumstances change; your agreement should have built-in mechanisms to adapt. Co-buying done properly is a legitimate and powerful strategy. Co-buying done carelessly is one of the most expensive mistakes you can make — financially and personally.
Disclaimer: The information provided in this article is for informational purposes only and should not be considered financial or legal advice. Property and lending laws in the United Kingdom vary and may change over time. We always recommend consulting with a qualified solicitor and mortgage broker before entering into a property purchase or financial arrangement with another party.
