If 2026 is the year you are moving in or buying a property with your partner, congratulations! However, have you considered the legal documents that could protect you if things don’t work out, or worse, if one of you were to die? While it may not be a very romantic thought, putting the right legal protections in place now can help prevent unnecessary stress and expense if your relationship breaks down or one of you dies.
When unmarried couples buy property together in England and Wales, two legal documents are often mentioned: a Declaration of Trust and a Cohabitation Agreement. Many assume these documents are interchangeable or that one covers everything. They don’t. Another big misconception is that if you have been living together for a long time, you will automatically be protected. You won’t.
In this blog, our family law team takes you through what you need to know.
The Uncomfortable Truth About Cohabitation
In England and Wales, there is currently no such thing as “common law marriage”. Simply living together, whether for two years or twenty, grants you almost no automatic legal rights to your partner’s property or finances.
When you buy property with someone you are not married to, the law does not automatically provide fairness. It looks at legal ownership (whose name is on the title deeds) and financial contributions (who paid what). Without clear documentation, the person who contributed less could walk away with half of everything, or the person who sacrificed more could be left with nothing.
This is where Declarations of Trust and Cohabitation Agreements become essential.
What Is a Declaration of Trust?
A Declaration of Trust (also called a Deed of Trust) is a legal document that records how you own a specific property and what share each person is entitled to.
What It Covers:
- Ownership shares – Who owns what percentage of the property.
- Financial contributions – Who paid the deposit, mortgage, or for property repairs and renovations.
- Division on sale – How proceeds will be split if you sell.
- Future contributions – How ongoing payments affect ownership.
- Death provisions – What happens to each person’s share if one of you dies.
Why You Need It:
When you purchase property jointly, you choose between two types of legal ownership:
- Joint Tenants – You both own 100% of the property together. If one dies, the survivor automatically inherits (regardless of your Will).
- Tenants in Common – You each own a specific percentage. Each person can leave their share to whoever they choose.
Most unmarried couples should choose Tenants in Common with a Declaration of Trust specifying the exact ownership split.
When Should You Consider a Declaration of Trust?
Unmarried couples who own a property together need a Declaration of Trust if:
- You are contributing unequal deposits.
- One person is paying a larger share of the mortgage.
- Family money is gifted toward the deposit.
- You want to protect your share for children from a previous relationship.
- One person owns the property, but the other is contributing financially.
What Is a Cohabitation Agreement?
A Cohabitation Agreement is a broader contract covering your entire financial and domestic relationship, not just property.
What It Can Cover:
- Property ownership (including multiple properties)
- Bank accounts, savings, investments
- Household expenses and bill-sharing
- Debts and liabilities
- Income management
- Children and financial support
- Pets (yes, seriously)
- Personal possessions and vehicles
- Pensions and business interests
- What happens if you separate
- Death provisions (though you still need a Will)
Why You Need It:
A Cohabitation Agreement creates the legal framework and financial fairness that the law doesn’t automatically provide to unmarried couples. It is a bespoke contract tailored to your circumstances.
When Should You Consider a Cohabitation Agreement?
Unmarried couples moving in together need a Cohabitation Agreement if:
- You are moving in together (renting or buying).
- One partner is reducing work hours or stopping work to care for children.
- You have significantly different incomes or assets.
- Either of you has children from previous relationships.
- You want to protect pre-relationship assets.
- One person is financially supporting the other through study or business start-up.
Do You Need Both?
These documents are not interchangeable; they complement each other. Think of the Declaration of Trust as protecting your property investment specifically, while the Cohabitation Agreement protects everything else in your shared life.
If you are buying property together, yes, you should consider both.
- The Declaration of Trust documents your property ownership and ensures Land Registry records are clear.
- The Cohabitation Agreement covers your other assets, day-to-day finances, possessions, and arrangements for children.
Exception: If you are renting (not buying), you only need a Cohabitation Agreement. If you already own separate properties and are moving in together without buying jointly, a Cohabitation Agreement remains essential.
What Happens Without These Documents?
The short answer: potentially, you may lose everything you have invested, or you may have no entitlement to the property at all.
Without a Declaration of Trust, if you and your partner own the property as Joint Tenants, your partner legally owns 50%, even if you contributed more, such as the deposit to buy the property. As a result, if you separate, your partner is legally entitled to half of the property’s value, regardless of separate contributions.
Without a Cohabitation Agreement, if you give up your career to raise children, for example, and the house is in your partner’s name, you would be entitled to child maintenance, but zero financial support for yourself if you separated.
If your partner dies without a Will and the property is in their sole name, you will not automatically inherit. You could be evicted from your family home.
Relationship Breakdown and Cohabitation Disputes
If your relationship has recently broken down, it is important that you have specialist advice as soon as possible regarding the division of your property and arrangements for your children.
This is a complex area of the law, as there is often a correlation between financial claims for children and property ownership. We can guide you through the process, including the likely approach the court will take if any dispute cannot be resolved amicably through negotiation or mediation.
How Rose Legal Can Help
Our family law team in Kingston upon Thames has extensive experience protecting cohabiting couples, including drafting Declarations of Trust, Cohabitation Agreements, and representing clients in cohabitation disputes.
Read some of our previous articles for further information:
- How to Present a Strong Trusts of Land and Appointment of Trustees Act 1996 Case.
- Love, Leases, Legalities – A Contemporary Companion to Cohabitation.
- What is a Cohabitation Agreement?
- Co-Ownership: Buying a House with a Friend or Partner.
- Property Disputes for Unmarried Couples – What is TOLATA?
Talk To Our Specialists
It is always important and highly advisable to seek professional legal advice to ensure the best course of action for your circumstances. Talk to our specialist team via the links below.
This blog post is not intended to be taken as advice or acted upon. If you are seeking legal advice, please contact our team of solicitors.
