Cohabitation agreements
A cohabitation agreement is a contract between two people who live together without being married. It documents who owns what, how money and expenses work during the relationship, and what happens to property and finances if the relationship ends.
Before we go further, one fact needs to land, because nearly everything else on this page flows from it: in most states, unmarried couples have almost none of the legal protections married couples take for granted. No equitable property division. No spousal support. No automatic inheritance rights. In most of the country, common-law marriage is a myth people believe right up until the day they need it to be true.
Marriage, whatever else it is, is a legal safety net woven from hundreds of default rules. Live together without marrying and you’re working without the net. A cohabitation agreement is how you build your own.
Who needs this? More couples than you’d think
Couples are building bigger lives outside marriage than any generation before them. Buying homes together. Running businesses together. Raising kids, blending finances, supporting each other through career changes and health scares. Decades-long partnerships, deliberately unmarried.
The law hasn’t caught up, and mostly isn’t trying to. So consider where you’d stand if the relationship ended tomorrow:
You bought a home together.
If both names are on the deed, you’re co-owners with no exit rules: no mechanism for a buyout, no agreement on what happens to unequal down payments, no plan for who keeps the house. If only one name is on the deed, the other partner may have contributed to the mortgage for years and walk away with nothing.
One of you earns, the other builds the life.
A partner who scaled back a career, moved cities, or ran the household has made an enormous investment with no legal recognition. A divorcing spouse in that position has support claims. An unmarried partner, in most states, has a moving truck.
You’ve mixed money.
Joint accounts, shared credit cards, one partner’s cash into the other’s business or property. Untangling commingled finances without a written framework is expensive, bitter work, and the default answer is usually “whoever holds title wins.”
One of you has real assets.
A business, family money, significant property. Ironically, an agreement protects this partner too, by cleanly separating what’s yours from what’s shared and cutting off creative claims later.
What does a cohabitation agreement cover?
The core topics:
Property ownership. What each of you brought in and keeps. How jointly acquired property is owned, in what shares, and what happens to it at a breakup: buyout terms, sale procedures, who moves out and on what timeline. For a shared home, this section alone justifies the document.
Financial responsibilities. How household expenses split, what happens with joint accounts, how big purchases get decided, whether money flowing from one partner to the other is a gift, a loan, or an investment. Writing it down now prevents the retroactive renegotiation that happens in every breakup.
Debt. Whose debts are whose, and a firewall so one partner’s liabilities don’t reach the other’s assets or credit.
Assets acquired along the way. The default in most states is brutally simple: title controls. The agreement can say something smarter, like recognizing contributions that don’t show up on a deed.
What happens at the end. Some couples include support terms, a transition period, or dispute-resolution steps. Enforceability of support-style promises between unmarried partners varies by state, so this section takes careful drafting.
What it generally can’t cover: child custody and child support. As with marital agreements, children’s issues are decided when they arise, based on the children’s interests, not by contract in advance.
The misconceptions that cost people
“After enough years, we’re basically married in the eyes of the law.” Only a small handful of states recognize new common-law marriages, and the requirements are stricter than the folklore suggests. In most states, fifty years together confers exactly the same legal status as five months. This misconception has cost people their homes.
“It won’t happen to us.” Maybe not. But you buy homeowner’s insurance without planning a fire. The agreement costs a fraction of one month of the litigation it prevents, and the conversation it forces, about money, expectations, and fairness, is one strong couples handle just fine. It’s worth noticing that the discomfort is the argument: if the topic is too fragile to discuss, that’s information too.
“We each keep our own accounts, so we’re fine.” Separate accounts don’t address the house, the appreciation, the renovations one of you paid for, the career one of you paused. Life commingles even when the checking accounts don’t.
Keeping the agreement current
A cohabitation agreement should grow with the relationship. New house, new business, a child, a big inheritance, one partner leaving the workforce: each is a reason to update. Amendments follow the same recipe as the original: written, signed, with both partners informed and advised. A quick review every few years keeps the document telling the truth.
And if you later decide to marry, the cohabitation agreement can hand off to a prenuptial agreement, often carrying its terms forward. Couples who’ve done the first find the second easy. The hard conversation is already behind them.
The role of counsel
The enforceability rules for agreements between unmarried partners vary by state, and technical details, disclosure, drafting precision, execution, matter. Each partner should have independent advice; an agreement both sides understood and negotiated fairly is dramatically harder to attack later. This is also simply a fairness point. The goal isn’t a document one of you wins. It’s a document both of you would sign again.
Straight answers.
Do unmarried couples have the same rights as married couples?
In most states, not close. No property division framework, no support rights, no automatic inheritance. The law mostly treats long-term partners as legal strangers, which shocks people at the worst possible moment.
Should we have an agreement if we’re buying a home together?
Yes. Unreservedly yes. A home is most couples’ largest asset, and co-owning one without exit terms is the single most common way unmarried breakups turn into litigation.
Can the agreement cover shared debts and expenses?
Yes. Who pays what monthly, how joint debt is handled, and how one partner’s obligations are kept away from the other’s assets and credit.
Can it protect property I owned before the relationship?
Yes, cleanly. It can confirm that premarital property, and often its appreciation, stays separate no matter how the household finances mingle.
What actually happens if we break up without an agreement?
Title mostly controls, contributions mostly don’t, and anything disputed heads toward general contract or property litigation, which is slower, costlier, and less predictable than family court. The partner who isn’t on the paperwork usually loses.
Can we modify the agreement later?
Yes, in writing, signed by both. Update it when life changes materially.
Do we each need our own lawyer?
Each of you should at least have independent review. It strengthens the agreement and ensures it’s fair, which is the point.
Let’s talk
If you’re building a life with someone, married or not, the assets you’re building deserve rules you chose. We’ll help you write them while it’s easy. It’s a shorter conversation than you think.
Brown Carrington helps families across Kentucky, Ohio, Indiana, Colorado, Georgia, and Florida.