Cohabitation agreements and property ownership: why legal advice matters

Cohabitation is increasingly common in England and Wales, with many couples choosing to live together and buy property without marrying or entering into a civil partnership.

However, unmarried couples do not have the same legal protections as married couples or civil partners if their relationship ends. When a couple owns property together, questions can arise over deposits, mortgage contributions, ownership shares, and responsibility for other costs, particularly when they never formally record their intentions.

If you are buying a property together, contact our solicitors early to understand your position and ensure your arrangements reflect your agreement.

Cohabitation and the changing legal landscape

Cohabitation has become increasingly common in England and Wales. According to the latest figures from the Office for National Statistics, the proportion of adults cohabiting without ever having married or entered into a civil partnership increased from 9.8% in 2015 to 10.8% in 2025.

Against this backdrop, the Government recently consulted on proposals to reform the law affecting cohabiting couples in England and Wales. A fairer end to relationships, which ran from 5 June to 14 August 2026, considered new statutory rights and protections for eligible cohabitants on separation and improved inheritance rights where a partner dies without a will.

These proposals are not yet law. Until reforms are introduced, unmarried couples still have fewer legal protections than married couples or civil partners, making it important to consider how financial and property arrangements are formally recorded.

What is a cohabitation agreement?

A cohabitation agreement is a legal document which records how a couple intends to manage their financial arrangements during their relationship and what should happen if they separate.

A cohabitation agreement can be tailored to the couple’s circumstances and cover a wide range of issues, including:

• Ownership of the family home
• Responsibility for mortgage payments and household bills
• Contributions towards improvements or renovations
• Ownership of savings and other assets
• Arrangements if the property is sold or one party wishes to leave

Although these conversations may not be at the forefront of a couple’s mind when buying a home together, agreeing how these matters will be dealt with at an early stage can prevent uncertainty and misunderstandings later. When arrangements are not clearly recorded, resolving a disagreement can also cost significantly more in legal fees than putting appropriate protections in place at the outset.

Although cohabitation agreements are commonly associated with couples, they are not limited to romantic relationships. They can also be used by people who live together as friends, siblings or other family members to record their respective financial and property arrangements.

Both parties should obtain independent legal advice before entering into a cohabitation agreement to ensure that they understand its effect and that their respective interests are properly protected.

Why does property ownership matter?

How a property is owned can have significant consequences if the couple later separates or one owner dies.

When a property is owned as joint tenants, both parties own it jointly and, if one owner dies, their interest passes automatically to the survivor. Where a property is owned as tenants in common, each party has a separate share in the property, which may be equal or unequal. That share will instead pass in accordance with the deceased owner’s will or, if there is no will, the intestacy rules.

This is particularly important for unmarried couples, as a surviving cohabitant does not automatically inherit under the intestacy rules. A cohabitation agreement should therefore be part of the wider consideration of a couple’s arrangements, alongside how the property is owned and appropriate, up-to-date wills.

The way in which ownership is structured should reflect the parties’ intentions, including how they have agreed their respective financial contributions will be treated.

What happens if one person contributes more than the other?

It is common for couples to contribute different amounts towards a deposit, mortgage payments or the cost of improving a property.

Problems can arise when contributions are made without any agreement about whether, or how, they should affect each person’s share in the property. If the property is later sold or the couple separates, the parties may have very different expectations about what they are entitled to receive.

A declaration of trust can be used alongside a cohabitation agreement to formally record the parties’ respective interests in the property and how the proceeds of a future sale should be divided.

Do unmarried couples have the same rights as married couples?

No. There is no such thing as a “common law marriage” in England and Wales, regardless of how long a couple has lived together.

Living with a partner does not, by itself, give someone an automatic interest in property owned solely by their partner. In some circumstances, a non-owning partner may be able to establish an interest in the property through trust law. Such claims can be complex and their outcomes uncertain, particularly when the parties never formally recorded their intentions.

This can become particularly important following separation, where one person has contributed financially to a property without their position being clearly documented. Recording the parties’ intentions at the outset can provide greater certainty and reduce the potential for disputes later.

Can ownership arrangements be changed later?

Yes. Couples may wish to review their arrangements as their circumstances change, for example after marriage, the birth of a child, receiving an inheritance, or a significant change in their respective financial contributions.

Depending on the circumstances, this may involve updating a cohabitation agreement or declaration of trust, changing the parties’ ownership shares, or transferring equity.

Taking advice when circumstances change can help ensure the legal arrangements continue to reflect what both parties intend.

For more information about adding a partner to an existing property, read our guide to adding a partner to your property.

What legal work is involved?

The legal work required depends on the couple’s circumstances and how they want to structure their arrangements. This may include:

• Preparing a cohabitation agreement
• Advising on whether to own a property as joint tenants or tenants in common
• Preparing a declaration of trust
• Recording unequal ownership shares
• Advising on transfers of equity or other changes to the ownership arrangements

What issues commonly lead to disputes?

Disagreements between cohabiting couples are not limited to who paid the larger deposit or contributed more towards the mortgage. Problems can arise in a variety of circumstances, particularly where expectations have not been formally recorded.

For example, one person may move into a property already owned by the other and contribute towards the mortgage or renovations without agreeing whether this will give them any share in the property. Contributions from one party’s family can also create uncertainty if the couple has not agreed how these should be reflected in their ownership arrangements.

Disagreements may also arise over whether a property should be sold, whether one person can remain in the home, or how ongoing costs should be met following separation. The arrival of children can significantly change a couple’s financial circumstances, particularly where one person reduces their working hours or takes on greater caring responsibilities, and may alter their expectations about what should happen to the family home.

Misconceptions about “common law marriage” can cause further difficulties, while disputes can extend beyond the property itself to furniture, valuable possessions or pets.

Recording expectations clearly, and reviewing them as circumstances change, can help prevent these issues from becoming disputes later.

Guidance from our solicitors

Property ownership can form part of a wider conversation about a couple’s financial arrangements, family circumstances and plans for the future.

Dominic Mercer, head of residential property at SO Legal, explains:

“Many couples still assume that living together gives them the same protection as marriage, but it does not. The Government’s consultation on cohabitation reform may change that in future, but until any reform becomes law, a cohabitation agreement, a declaration of trust and up-to-date wills remain the most effective way for couples to protect themselves and each other.”

With expertise in residential property and family law, our solicitors can advise on the property and broader legal implications of living together, helping couples put arrangements in place that accurately reflect their intentions.

Whether you are buying a property with a partner or reviewing arrangements already in place, our solicitors can explain your options and help you decide which protections suit your circumstances.