Cohabitation property rights for unmarried couples are almost entirely what you build for yourselves. Marriage triggers a default framework for dividing assets, inheriting from each other, and stepping in during a medical crisis. Living together, no matter how long, triggers none of it. If you want your partner to keep the house, inherit the retirement account, or make medical decisions when you can’t, you have to put that in writing while you’re both healthy and on good terms.
What You Don’t Get Automatically
Married couples operate inside a legal framework that runs on its own. Divorce courts divide property under community property or equitable distribution rules. A surviving spouse inherits a share of the estate even without a will. Spouses qualify for Social Security survivor benefits, take FMLA leave to care for each other, and move unlimited assets between themselves tax-free during life and at death.
None of that applies to unmarried partners. When you split up, there is no family court process to divide what you own. When one partner dies without a will, the survivor has no legal claim to anything, regardless of how long the two of you lived together or how tangled your finances became. The law treats you as legal strangers until you take specific steps to change that.
The Common-Law Marriage Exception
A small group of states still recognize common-law marriage, which grants full marital rights to couples who never held a ceremony or obtained a license. Roughly ten states and the District of Columbia currently allow new common-law marriages to form, including Colorado, Iowa, Kansas, Montana, South Carolina, Texas, and Utah.
The bar is higher than most people assume. Living together for years, on its own, does not create a common-law marriage anywhere. Both partners must actually intend to be married and present themselves publicly as spouses, through shared last names, joint tax returns, or referring to each other as husband or wife. If you think your relationship might qualify, talk to a family law attorney in your state before you rely on it, because the difference between common-law married and unmarried is the difference between full protection and almost none.
How You Hold Title
The single most consequential decision unmarried couples make is how their names appear on the deed. The deed controls ownership, and the choices are not interchangeable.
Joint Tenancy
Joint tenancy gives both partners equal ownership shares and includes a right of survivorship. If one partner dies, the other automatically becomes the sole owner without probate. That’s attractive when you want the survivor to keep the home no matter what. The tradeoff is rigidity: both owners must agree on selling or refinancing, and neither can leave their share to someone else in a will.
Tenancy in Common
Tenancy in common lets partners own unequal shares, which fits when one person is contributing significantly more to the purchase. A 70/30 split can mirror actual down payment or income contributions. Each owner can sell or transfer their share independently and can leave that share to anyone through a will. There is no survivorship, though, so a deceased partner’s share goes through probate and lands with whoever they named or, without a will, with blood relatives.
Tenancy by the Entirety Is Not Available
A third form of co-ownership, tenancy by the entirety, offers strong creditor protection and automatic survivorship, but the states that recognize it limit it to married couples. Unmarried partners cannot use it.
One Name on the Deed
When only one partner’s name is on the title, that partner owns the property outright. The other has no ownership interest, even after years of paying half the mortgage. If the relationship ends, the non-titled partner’s only recourse is an equitable claim in court, which is uncertain and expensive. If you go this route, a written cohabitation agreement documenting each partner’s rights is not optional.
Cohabitation Agreements
A cohabitation agreement is a contract between unmarried partners that spells out who owns what, how expenses are shared, and what happens to property if the relationship ends. It functions as the private version of the legal framework marriage provides automatically. You can address how jointly purchased property gets divided, whether one partner is entitled to reimbursement for mortgage payments on the other’s home, and how shared debts are handled.
Enforceability varies by state, but courts generally uphold these agreements when they meet basic contract requirements: in writing, signed voluntarily, and based on honest financial disclosure. Texas strictly requires a written agreement. Most other states will recognize oral agreements in theory, but proving the terms of an oral deal years later is hard enough that written is the only reliable option.
Courts sometimes refuse to enforce agreements that are heavily one-sided or signed under pressure. Each partner consulting their own attorney before signing strengthens the agreement significantly, because it forecloses any later argument that one partner didn’t understand what they were signing.
If You Never Signed Anything
When a couple never put anything in writing and one partner contributed money or labor to property titled in the other’s name, courts have equitable doctrines that can produce a remedy. They are the safety net, not the plan.
A constructive trust is a court-imposed remedy that recognizes a non-titled partner’s interest in property. If you paid for major renovations on your partner’s home, or made years of mortgage payments on a house only in their name, a court can rule that your partner holds a portion of the value in trust for you. You have to show a shared understanding that you would have an ownership interest, and that you relied on that understanding to your detriment.1Justia Law. Marvin v. Marvin
Unjust enrichment is different. Instead of establishing an ownership share, it seeks compensation for a benefit the other partner accepted and would be unfair to keep without paying for. Courts look at the nature of the contributions, any promises made, and the dynamics of the relationship.
One important limitation: domestic labor like cooking, cleaning, and childcare is much harder to recover for than financial contributions. Legal scholarship and the Restatement (Third) of Restitution have noted that the value of traditional domestic services is often excluded from jointly created assets in unjust enrichment analysis. A partner who took on more of the household work while the other built equity has entered a riskier arrangement than they may realize. A cohabitation agreement that explicitly values those contributions is the fix.
If you co-own property and can’t agree on what to do with it, either partner can file a partition action asking a court to divide or sell it. Courts consider each partner’s financial contributions to the purchase, mortgage payments, property taxes, insurance, and improvements, so the split is not always 50/50. Partition actions typically run $10,000 to $30,000 in attorney fees and costs and take months. A well-drafted cohabitation agreement with clear division terms avoids this entirely.
Death and Incapacity
The gap between married and unmarried couples is starkest at death. If your unmarried partner dies without a will, you inherit nothing. Intestacy laws pass assets to blood relatives (children, parents, siblings) and do not recognize unmarried partners.2Justia. Protecting Unmarried Partners Through Estate Planning and Related Legal Strategies
Wills and Trusts
A will that names your partner as a beneficiary is the most direct protection. Without one, your partner has no legal standing to claim any part of your estate. Wills go through probate, which is public, slow, and open to challenge from family members. For larger estates or contentious families, a revocable living trust offers more privacy and is harder to contest.
Beneficiary Designations
Certain assets pass outside a will through beneficiary designations. Life insurance policies, retirement accounts, and many bank and investment accounts let you name a specific person to receive the funds at your death. These designations override whatever your will says, so they need to line up with the rest of your plan.2Justia. Protecting Unmarried Partners Through Estate Planning and Related Legal Strategies Review them regularly. People often name a partner early on and forget to update after a breakup, or name a parent years ago and never revisit it after moving in with someone new.
Transfer-on-Death Deeds
About 29 states and the District of Columbia allow transfer-on-death deeds (sometimes called beneficiary deeds) for real property. You name someone to receive your home at your death, keep full ownership and control while you’re alive, and the transfer happens automatically outside probate. For unmarried couples who own property separately, this can be a simpler alternative to a trust.
Healthcare and Financial Powers of Attorney
If your partner becomes incapacitated, you have no automatic authority to make medical or financial decisions for them. Most states give that power to spouses first, then parents, then adult children. An unmarried partner ranks below all of them, and in many states isn’t on the list at all.
Two documents solve this. A healthcare power of attorney lets your partner make medical decisions for you. A durable financial power of attorney lets them manage your money and pay your bills. Without them, your partner could be shut out of the hospital while an estranged parent makes the calls. Both documents are inexpensive to prepare and belong at the top of every unmarried couple’s list.
Tax Costs You Should Know About
The tax code is built around marriage, and unmarried couples pay more in several situations.
Married spouses can transfer unlimited assets between themselves during life and at death without gift or estate tax. Unmarried partners get no such benefit. The IRS defines spouse to include legally married same-sex couples but explicitly excludes domestic partners and those in civil unions.3Internal Revenue Service. Frequently Asked Questions on Gift Taxes The federal estate tax marital deduction, which lets a surviving spouse inherit any amount tax-free, does not apply to unmarried partners.4Office of the Law Revision Counsel. 26 U.S. Code 2056 – Bequests, Etc., to Surviving Spouse In 2026, the federal estate tax exemption is expected to drop to roughly $7 million per person after the Tax Cuts and Jobs Act’s temporary increase expires. Amounts above that threshold passing to an unmarried partner are taxed at rates up to 40%. A spouse would owe nothing.
For lifetime gifts, unmarried partners can give each other up to $19,000 per year in 2026 without filing a gift tax return. Anything more counts against the lifetime exemption. Married couples face no such cap.
When you sell a primary residence, federal law lets you exclude up to $250,000 of capital gains from income; married couples filing jointly can exclude up to $500,000. Two unmarried co-owners each get their own $250,000 exclusion, so together they can also reach $500,000, but only if each independently meets both the ownership and use tests: owning and living in the home for at least two of the five years before the sale.5Internal Revenue Service. Sale of Your Home If only one partner is on the title, only that partner claims the exclusion, no matter who paid the mortgage or lived there.
Federal Benefits You Cannot Access
A surviving spouse can collect Social Security benefits based on the deceased partner’s earnings record. An unmarried surviving partner cannot, no matter how long the relationship lasted or how financially dependent they were. The Social Security Administration generally requires at least nine months of marriage for survivor benefit eligibility.6Social Security Administration. Survivors Benefits for Same-Sex Partners and Spouses
The federal Family and Medical Leave Act gives eligible employees up to 12 weeks of unpaid, job-protected leave to care for a spouse with a serious health condition. Unmarried partners, including those in registered domestic partnerships and civil unions, are not spouses under the FMLA and do not qualify.7U.S. Department of Labor. Fact Sheet 28L – Leave Under the Family and Medical Leave Act When You and Your Spouse Work for the Same Employer Some states and employers extend similar protections to domestic partners, but there is no federal guarantee.
Shared Debt
One area actually works in your favor. You are generally not liable for your partner’s debts. The doctrine of necessaries, which exists in roughly 40 states and can make spouses responsible for each other’s medical bills and essential living expenses, almost never applies to unmarried partners. If your partner runs up credit card debt or faces a lawsuit, creditors cannot come after your separate assets.
The exception is any debt you have actually co-signed or jointly applied for. A joint credit card, a lease with both names, or a mortgage you both signed makes both partners fully liable regardless of relationship status. Before you co-sign anything, understand that you’re on the hook for the full balance if your partner stops paying, and a breakup does not change that.
A Practical Checklist
Protection for unmarried couples is less about any single document and more about layering coverage for different scenarios. At minimum, partners living together should put the following in place:
- A cohabitation agreement covering property division, expense sharing, and what happens at separation.
- A deliberate title choice (joint tenancy or tenancy in common), with ownership shares that reflect actual contributions.
- Wills or trusts naming your partner as a beneficiary. Without them, intestacy laws exclude your partner entirely.
- Updated beneficiary designations on life insurance, retirement accounts, and bank accounts.
- A healthcare power of attorney authorizing your partner to make medical decisions if you’re incapacitated.
- A durable financial power of attorney letting your partner manage bills and accounts if you can’t.
- A transfer-on-death deed if your state allows one and you own property separately.
None of these documents is expensive on its own. An attorney can prepare most of them together for far less than the cost of litigating a single property dispute after a breakup. The couples who run into trouble aren’t the ones who couldn’t afford the paperwork. They’re the ones who assumed they’d figure it out later.