Is a cohabitation agreement legally binding?

Yes, in most states a cohabitation agreement is enforceable as a regular contract, provided it is in writing, both partners signed it voluntarily, each disclosed their finances honestly, and the terms are not unconscionable. Because enforcement rules vary, the agreement should name a governing state, and high-asset couples often have each partner review it with separate counsel.

What is the difference between a cohabitation agreement and a prenup?

A prenuptial agreement takes effect only if the couple marries and is governed by marriage-specific statutes. A cohabitation agreement governs unmarried partners who live together and relies on ordinary contract law. Couples who later marry usually replace the cohabitation agreement with a prenup, since the legal frameworks are different.

Do unmarried couples really need a cohabitation agreement?

If you share rent, a mortgage, bank accounts, debts, pets, or major purchases, a cohabitation agreement protects both of you. Unmarried partners have almost no automatic legal rights to shared property or support if they separate, so without a written agreement, dividing assets after a breakup can be expensive and contentious.

Can a cohabitation agreement cover what happens if one partner dies?

It can address jointly owned property and shared belongings, but it cannot replace a will or beneficiary designation. Unmarried partners do not inherit automatically, so a cohabitation agreement should work alongside estate documents (a will, beneficiary forms, and possibly a power of attorney) rather than try to substitute for them.

Does a cohabitation agreement have to be notarized?

Notarization is not strictly required for enforceability in most states, but it is strongly recommended. A notarized, dated agreement helps prove that both partners signed voluntarily, which is one of the most common points of dispute. Each partner should keep a signed copy.

Cohabitation Agreement Template Guide

Learn how to write a cohabitation agreement for unmarried couples. Covers property, debts, expenses, separation terms, and what makes the contract enforceable.

Moving in together is a financial decision as much as a romantic one. The moment two people share rent, a lease, a bank account, a car loan, or a pet, they create a web of obligations that the law treats very differently for unmarried couples than for married ones. A cohabitation agreement is the contract that sorts all of it out in advance, calmly, while everyone is still on good terms.

This guide explains what a cohabitation agreement is, what to put in one, how to write it step by step, and the mistakes that cause these agreements to fall apart when they're needed most.

What is a cohabitation agreement?

A cohabitation agreement is a written contract between two unmarried people who live together. It defines who owns what, who pays for what, and how property, debts, and shared expenses will be divided if the relationship ends or one partner dies.

Married couples are protected by decades of family law: rules for dividing marital property, spousal support, and inheritance all kick in automatically. Unmarried partners get almost none of that. In most states, if you split up, you walk away with whatever is in your name, regardless of who actually paid for it or how long you were together. A cohabitation agreement fills that gap by spelling out the couple's own rules.

It's sometimes called a living-together agreement, a domestic partnership agreement, or a non-marital agreement. The name matters less than the function: turning informal assumptions into enforceable terms.

Who needs one?

You don't need to be wealthy to benefit. A cohabitation agreement makes sense whenever partners are financially intertwined:

You're renting or buying a home together and want to clarify who is responsible for the lease or mortgage
One partner contributes more to a down payment, renovation, or furniture
You share bank accounts, credit cards, or a car loan
One partner supports the other while they study, job-hunt, or raise children
You own pets together and want to decide custody in advance
You're blending finances but want to keep certain assets separate

If you're weighing the differences between simply living together and a more formal legal status, it's worth understanding how the law already treats your situation. Our explainer on the difference between domestic partnership and common-law marriage is a good starting point before you draft anything.

What to include in a cohabitation agreement

A strong cohabitation agreement is specific. Vague promises ("we'll split things fairly") are exactly what courts can't enforce. Cover each of the following.

1. Identification of the parties and the relationship

Name both partners with full legal names and current address. State that the parties are unmarried, intend to live together, and are entering the agreement voluntarily. Note that the agreement does not create a marriage or common-law marriage.

2. Property owned before moving in

List each partner's separate property, the assets they bring into the relationship and intend to keep solely their own. This commonly includes savings, vehicles, investments, retirement accounts, and any real estate owned before cohabitation. Separate property stays separate unless the agreement says otherwise.

3. Jointly acquired property

Decide how property bought during the relationship will be owned. For each major category (furniture, electronics, vehicles, a shared home), specify:

Whose name the asset is titled in
The percentage each partner owns
How it will be divided or bought out if the couple separates

If you're buying a home together, this is the most important section. Couples who purchase property without writing down their ownership shares routinely end up in court; the issues mirror those faced by friends who co-buy real estate, which we cover in the legal considerations of buying property with friends.

4. Income, expenses, and household contributions

Spell out how the couple splits everyday costs:

Rent or mortgage payments
Utilities, groceries, and household supplies
Insurance and shared subscriptions
Whether contributions are equal, proportional to income, or based on some other formula

Being explicit here prevents the slow-burning resentment that builds when one partner feels they're carrying more than their share.

5. Debts

Address debts brought into the relationship and debts taken on together. State that each partner remains responsible for their own pre-existing debt, and decide how jointly incurred debt (a shared credit card, a co-signed loan) will be repaid and divided.

6. Loans between partners

If one partner lends the other money for a car, tuition, or a business, treat it like the loan it is. Document the amount, repayment terms, and whether interest applies. The same logic that protects friends and family applies here; our guide to a personal loan agreement between friends shows how to record a loan without poisoning the relationship.

7. Bank accounts

Clarify which accounts are joint and which are separate, who can access them, and how a joint account would be divided on separation.

8. Pets

Pets are property in the eyes of the law, but they're family to most couples. Decide in advance who keeps the pet, who covers veterinary costs, and whether the other partner gets visitation. Settling this while everyone is calm avoids an ugly fight later.

9. What happens if the relationship ends

This is the heart of the agreement. Lay out:

How shared property and debts are divided
Whether either partner owes the other any support payments, and for how long
How long a partner has to move out of a shared home
A method for resolving disputes: mediation before litigation is a common, cost-saving choice

10. What happens if a partner dies

A cohabitation agreement can address jointly owned property, but it cannot replace a will. Unmarried partners do not inherit automatically. Note in the agreement that each partner will maintain their own estate documents, and make sure you actually have them.

11. Governing law, amendment, and signatures

Name the state whose law governs the agreement, require that any changes be made in writing and signed by both partners, and provide signature lines. Date the agreement and have it notarized.

How to write a cohabitation agreement: step by step

Step 1: Talk it through first. The conversation matters more than the paperwork. Agree on the big principles (separate vs. shared property, how expenses split, what happens on a breakup) before anyone starts drafting.

Step 2: Inventory your finances. Each partner lists their assets, income, and debts. Honest, complete disclosure is a legal requirement; hiding assets is one of the fastest ways to get an agreement thrown out.

Step 3: Draft the terms. Work through each section above. Use plain, specific language. Numbers, percentages, and deadlines beat adjectives every time.

Step 4: Review separately. For couples with significant assets, each partner should have the agreement reviewed by their own lawyer. Independent review is strong evidence that both signed voluntarily and understood the terms.

Step 5: Sign and notarize. Both partners sign in front of a notary, and each keeps a dated, signed copy.

Step 6: Revisit it after major changes. Buying a home, having a child, a big change in income, or marriage should all trigger a review. If you marry, you'll typically replace the cohabitation agreement with a prenuptial agreement. Our prenuptial agreement checklist walks through what changes when you do.

Common mistakes to avoid

Relying on a verbal understanding. "We agreed she'd get the car" means nothing without a signature. If it isn't written down, it doesn't exist as far as a court is concerned.

Hiding or omitting assets. Incomplete financial disclosure is grounds to void the entire agreement. Disclose everything, even the assets you intend to keep separate.

Including non-financial terms. Clauses about household chores, who cooks, or personal behavior aren't enforceable and make the document look unserious. Keep it to property, money, and obligations.

Signing under pressure. An agreement presented as an ultimatum the night before a move can be challenged as coerced. Give both partners time to read, question, and seek advice.

Trying to make it a will. A cohabitation agreement governs the living relationship; it can't direct inheritance. You still need separate estate documents.

Using terms so vague they can't be enforced. "We'll divide things fairly" invites exactly the dispute the agreement is supposed to prevent. Be concrete.

Cohabitation agreement vs. prenuptial agreement

The two are easy to confuse, but they operate in different legal worlds. A prenuptial agreement only takes effect if a couple marries and is governed by marriage-specific statutes that dictate disclosure, fairness, and enforceability. A cohabitation agreement applies to unmarried partners and is enforced under ordinary contract law.

If you're living together with no plans to marry, the cohabitation agreement is your tool. If marriage is on the horizon, plan to draft a prenup as well. The cohabitation agreement won't automatically carry over once you say "I do."

Is a cohabitation agreement enforceable?

In most states, yes, courts treat it like any other contract. To hold up, it generally must be:

In writing and signed by both partners
Supported by full, honest financial disclosure from each side
Entered voluntarily, without fraud, duress, or pressure
Fair enough that no term is unconscionable
Limited to lawful, financial subject matter

A handful of states are stricter about agreements between unmarried partners, which is why naming a governing state and, for higher-asset couples, having independent legal review are both worth the effort. Notarization isn't always required, but it strengthens the record that both partners signed willingly.

Related guides

Generate Your Cohabitation Agreement with Contractable

A cohabitation agreement only works if it covers your actual situation (your home, your debts, your accounts, your pets) in language a court will enforce. Contractable builds a customized cohabitation agreement in minutes: property division, expense splits, separation terms, and the clauses that keep it enforceable, all tailored to the two of you. No lawyer or legal background required. Just clear answers to a few questions and a finished agreement ready to sign.