Buying a Home With a Partner When You're Not Married in Washington

You’re not married, you’re buying a house together, and somewhere between the pre-approval and the offer someone — a parent, a lawyer friend, a podcast — asked the awkward question: what happens to the house if you split up?

It’s the right question, asked at the right time. Married couples get a default legal framework for free: Washington’s community property system plus divorce courts to divide things if it ends. Unmarried couples get no automatic framework — which means you’re either going to write your own rules now, while you like each other, or discover the gaps later, when you don’t. The good news: writing your own rules is neither expensive nor unromantic. It’s a deed choice and a document.

Here are the decisions, in the order they’ll come at you.

Decision 1: How you’ll hold title

When two unmarried people buy together in Washington, the deed will typically vest in one of two forms:

Joint tenancy with right of survivorship (JTWROS). You each own the whole thing together, and if one of you dies, the survivor automatically owns it all — outside of any will, outside of probate. That last part is the headline: right of survivorship overrides your will. For committed partners who want each other protected, that’s a feature. For partners who’d want their share to go to their kids or family, it’s a serious problem.

Tenancy in common (TIC). You each own a defined share — 50/50, 70/30, whatever you choose — and your share is yours: you can leave it to anyone in your will, and it passes through your estate, not automatically to your co-owner. The flip side: if one partner dies without a will, their share goes to their legal heirs under intestacy rules — which, for unmarried partners, means not you. You could end up co-owning your home with your partner’s siblings.

There’s no universally right answer. Survivorship protects the partner; tenancy in common protects unequal stakes and outside heirs. Decide deliberately, tell the escrow officer how to vest title, and back the choice with wills either way — an estate-planning attorney can square the deed, the wills, and your intentions in a single short engagement.

Decision 2: What unequal contributions mean

The most common real-world setup: one partner brings most of the down payment, or earns more, or one has great credit and the other has a 12-year-old collections account. Mechanics worth knowing:

• Mortgage and title are separate. A couple can both be on title while only one is on the loan (the strong-credit partner qualifying alone). But understand what that creates: one person carries all the debt liability while two people own the asset. Workable — if the written agreement (next section) addresses who pays what and what happens on a split.
• Both on the loan means both fully liable. Lenders don’t recognize “we agreed I’d pay 70%.” If your partner stops paying, the lender expects you to cover all of it, and both credit scores ride on every payment.
• Unequal down payments deserve unequal protection. If one of you puts in $150,000 of inheritance and the other $10,000, a 50/50 deed with no agreement just silently gifted $70,000. TIC shares or a written reimbursement-first provision fixes this in one paragraph.

One more Washington-specific wrinkle: for couples in long, marriage-like relationships, Washington courts recognize what’s called a committed intimate relationship doctrine and can equitably divide property acquired during the relationship if it ends — meaning long-term unmarried partners may have more entangled rights than they assume, just less predictable ones. This cuts both ways and is precisely why writing down your actual intentions beats relying on either “we’re not married so it’s simple” or default doctrine. An hour with a family-law attorney is the move if your situation is long-running or asset-heavy.

Decision 3: The co-ownership agreement (the part everyone skips)

This is a short contract — a “cohabitation agreement” or “co-ownership agreement,” drafted by an attorney — that answers the questions a breakup or a death would otherwise litigate:

• Ownership shares and how contributions (down payment, mortgage, improvements) are credited
• Who pays what monthly — mortgage, taxes, insurance, utilities, repairs — and what happens when someone can’t
• The exit mechanics: if you split, who has the right to buy the other out, at what valuation method (appraisal, average of two, etc.), on what timeline — and if neither can buy, the house gets sold and proceeds split per the shares
• Death provisions that match your deed-and-wills choices
• The deadlock-breaker: what happens when one wants to sell and one doesn’t (without an agreement, the legal backstop is a court partition action — slow, expensive, and adversarial)

Couples resist this document because negotiating a breakup clause feels like planning to fail. Reframe it: it’s the same reason the house has fire insurance. Most couples never use it; the ones who need it really need it. And the negotiation itself — money habits, expectations, fairness — is genuinely useful pre-merger due diligence.

The buying process itself is the normal one

Pre-approval (joint or single), touring, offers, inspection, escrow — all standard; our Seattle home buying guide walks the full sequence, and it’s worth pressure-testing the payment on two incomes — and on the scarier one-income scenario — with a mortgage calculator before you set a budget. Two notes specific to co-buyers:

• Buy at the price the relationship can carry, not the maximum two incomes qualify for. A house that requires both paychecks forever is also a house that makes every future life change — grad school, a startup, a breakup — a housing crisis.
• Decide your agent-and-fee approach together. Post-NAR-settlement, buyer-agent compensation is explicitly negotiable, and what you’ll pay for representation is a real budget line. Seeing what agents actually charge is exactly what Manaky Homes is for — a free marketplace where Greater Seattle agents publish their fees side by side. Get on the waitlist before you start touring.

Mistakes unmarried co-buyers make

• Vesting title on autopilot. The deed form gets chosen in a 30-second escrow conversation and quietly determines who inherits the house. Choose it on purpose.
• One name on title “for simplicity.” The off-title partner who pays half the mortgage for six years has been building someone else’s equity, with at best a messy doctrine-based claim to show for it.
• No wills. For unmarried partners, intestacy law is the villain of every cautionary tale. Two simple wills are cheap.
• Handshake economics. “We’ll figure out the percentages later” — later being the worst possible time, with the most possible resentment.
• No deadlock clause. The one-wants-to-sell standoff is the most common co-ownership failure, and a partition lawsuit is the most expensive way to resolve it.
• Skipping professional advice to save a few hundred dollars on a transaction with two unprotected six-figure stakes. The attorney consult is the cheapest insurance in this entire purchase.

The bottom line

Unmarried couples can absolutely buy well together in Washington — they just have to build, on paper, the framework that marriage would have supplied by default: a deliberate deed, wills that match it, and a short agreement covering money in and money out. Do those three things while you’re happy, and the house becomes what it should be: the home you chose together, not a contingent liability with a kitchen.