What Is a Cohabitation Agreement? When to Get One and What to Include

You’ve found a place together. You’ve talked about how you’ll split the rent and who pays for what. Maybe you’ve read about what UK law doesn’t protect for cohabiting couples and realised that, without marriage or a civil partnership, you’re not automatically entitled to each other’s property, pension, or estate. So you’re wondering: what is a cohabitation agreement, and do we need one?

This guide explains what a cohabitation agreement is, what it typically covers, when it makes sense to get one in the UK, how it differs from other documents, and how to create one. It’s a practical step many couples take to protect themselves and each other—without getting married.

What is a cohabitation agreement?

A cohabitation agreement is a legal document for unmarried couples who live together (or plan to). It sets out how you’ll handle finances, property, and other practical matters during your relationship and, if it ever happens, if you separate.

In the UK, unmarried cohabiting partners have very few automatic legal rights compared with married couples or civil partners. There’s no such thing as “common-law marriage” in English, Welsh, Scottish, or Northern Irish law. A cohabitation agreement doesn’t give you the same status as marriage, but it does put your intentions in writing so that you both know where you stand and so that courts can take the agreement into account if there’s a dispute.

The agreement is usually drawn up with the help of a solicitor. In England and Wales it’s a contract between you and your partner; in Scotland, cohabitation agreements are specifically provided for in law (the Family Law (Scotland) Act 2006). The principles are similar: you’re recording what you’ve agreed so that it’s clear and, where possible, legally recognised.

What a cohabitation agreement typically covers

What you include is up to you, but most cohabitation agreements in the UK cover some or all of the following.

Property and ownership — Who owns the home you live in (or will own it)? If one of you already owned it before you moved in, does the other have any claim based on contributions (e.g. mortgage payments, renovations)? How will you deal with the property if you separate—who stays, who moves out, how is the equity split?
Financial contributions — How you’ll share day-to-day costs: rent or mortgage, bills, council tax, groceries, and other household expenses. You might refer to a moving-in checklist or your own spreadsheet; the agreement can summarise the principle (e.g. 50/50, or proportional to income).
Debts — How existing debts are treated (whose name they’re in, who is responsible) and how you’ll handle new joint commitments (e.g. a joint mortgage or loan).
Separation — What happens if you split up: who leaves the property, how assets and savings are divided, whether one person will pay the other anything (e.g. to reflect contributions to the home), and how you’ll handle joint debts.
Children — If you have or plan to have children, you can set out intentions about care and financial support. Note that the courts have wide powers over children; the agreement can record your intentions but won’t override what a court decides is in the child’s best interests.
Review — Many agreements say they’ll be reviewed when circumstances change (e.g. you buy a property together, have a child, or one of you stops working). That keeps the document relevant over time.

You don’t have to cover everything. You can start with the issues that matter most to you (often property and money) and add or amend later with legal advice.

When to get a cohabitation agreement

There’s no single “right” moment. It depends on your situation.

Before or when you move in — If one of you already owns the property or is contributing more to the deposit or rent, an agreement can clarify what happens to that money and to the property if you separate. It’s easier to agree when you’re both on good terms.
When you’re buying together — Buying a home is a big step. A cohabitation agreement can sit alongside the mortgage and conveyancing and set out how you’ll split the equity, who pays what, and what happens if one of you wants out or you split up.
When one of you contributes more — If one partner is paying the full mortgage or putting in a much larger deposit, the agreement can record whether that gives them a larger share of the property and how that’s calculated.
When circumstances change — You had no agreement when you moved in, but now you’re buying a place, having a child, or one of you is giving up work. That’s a good time to put something in writing.

Not every couple needs one. If you’re renting short-term, splitting everything equally, and don’t own assets together, you might decide it’s not necessary yet. But if there’s property, unequal contributions, or the possibility of conflict later, an agreement can reduce uncertainty and protect you both.

How a cohabitation agreement differs from other documents

Cohabitation agreement vs will — A will says what happens to your assets when you die. A cohabitation agreement deals with how you live together and what happens if you separate. They do different jobs; many cohabiting couples have both.
Cohabitation agreement vs marriage or civil partnership — Marriage and civil partnership give you a wide set of legal rights (e.g. on death, divorce, and tax). A cohabitation agreement doesn’t create that status. It only records what you’ve agreed between you and can help if you separate or if there’s a dispute.
Cohabitation agreement vs prenup — A prenuptial agreement (or prenup) is for people who are about to marry (or enter a civil partnership). It sets out how assets would be divided if they divorce. A cohabitation agreement is for couples who are not marrying (or not yet). If you later decide to marry, you might replace or supplement it with a prenup.

How to create a cohabitation agreement in the UK

Agree in principle — Both of you need to want to do it. Frame it as protecting both of you and reducing future conflict, not as “I don’t trust you.” If the idea feels uncomfortable, talking about money and legal steps first can help.
List what you want to cover — Use the sections above as a starting point. Write down the main points: property, contributions, separation, and anything else that matters to you.
See a solicitor — A cohabitation agreement should be drafted (or at least reviewed) by a solicitor so it’s clear and more likely to be upheld. Costs vary; a straightforward agreement might be in the region of £200–£500, but get a quote. Each of you should have independent legal advice—that is, your own solicitor—so the agreement is less likely to be challenged later.
Put it in writing — The solicitor will draft the document. You both sign it. Keep copies in a safe place.
Review when things change — If you buy a property, have children, or your finances change significantly, review the agreement and update it if needed.

Laws and costs apply to England and Wales; Scotland and Northern Ireland have their own rules. A local solicitor can advise on your situation.

Common concerns

“Does getting a cohabitation agreement mean we don’t trust each other?”

Many couples feel that way at first. But an agreement isn’t about assuming the worst. It’s about being clear so that neither of you is left guessing—or worse, arguing—if life changes. It can actually reduce stress: you’ve already had the conversation and written it down. Think of it like having the money conversation: it’s an act of care, not doubt.

“What if we get married later?”

If you marry or form a civil partnership, the cohabitation agreement may no longer apply in the same way; marriage brings its own legal framework. You can then consider a prenuptial or postnuptial agreement. Your solicitor can explain the options.

The bottom line

A cohabitation agreement is a legal document that sets out how you and your partner will handle property, money, and other practical matters while you live together—and what you’ve agreed should happen if you separate. In the UK, where unmarried cohabiting couples have few automatic rights, it’s a practical way to protect yourselves and each other.

The right time to get one is when it fits your situation: before or when you move in, when you buy together, or when your circumstances change. You don’t have to cover everything; you can start with what matters most and review it over time. With independent legal advice and a clear, written agreement, you’re not preparing for failure—you’re making sure you’re both on the same page.

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Thank you for reading 💜