What Is a Prenuptial Agreement?

A prenuptial agreement is a contract two people sign before they marry, deciding in advance how their property, debts, and financial support will be handled if the marriage ends. It is one of the most misunderstood documents in family law, and in Washington its enforceability depends less on the paper itself than on how fairly it was made. For a focused explanation, read when Should I Get a Prenuptial Agreement.

The Basic Idea

At its core, a prenuptial agreement, often called a prenup, is a private contract between two future spouses. It typically addresses who owns what, how property acquired during the marriage will be treated, how debts will be allocated, and whether either spouse will pay or receive spousal support if the marriage dissolves. Couples use prenups for many reasons: protecting a family business, clarifying expectations when one person brings substantial assets or debts into the marriage, providing for children from a prior relationship, or simply agreeing on the financial ground rules before saying "I do."

A prenup is not a prediction that the marriage will fail. It is a planning tool, much like a will or an insurance policy. Many couples find that the honest financial conversation required to build one actually strengthens the relationship, because it forces both people to be transparent about money before they merge their lives.

Why Washington's Community Property System Matters

To understand what a prenup does, you have to understand the default rules it is written against. Washington is a community property state. Under RCW 26.16.010, property a spouse owns before marriage, and property acquired afterward by gift, inheritance, or devise, is that spouse's separate property. But under RCW 26.16.030, property acquired during the marriage by either spouse is generally community property, owned equally by both. In other words, absent an agreement, what you earn and acquire during the marriage largely belongs to both of you.

A prenuptial agreement lets a couple rearrange those default rules. They might agree that certain earnings stay separate, that a business one spouse founded remains that spouse's alone, or that property will be divided in a particular way rather than under the usual community property presumptions. The community property statutes are the backdrop, and the prenup is the couple's negotiated departure from that backdrop.

Washington Has No Prenup Statute, So the Courts Set the Rules

Here is a point that surprises many people. Washington does not have a specific statute that governs prenuptial agreements the way some other states do. Instead, whether a prenup will be enforced is decided under case law developed by the Washington courts. The leading case is In re Marriage of Matson, 107 Wn.2d 479, 730 P.2d 668 (1986), and the Washington Supreme Court reaffirmed and applied that framework more recently in In re Marriage of Bernard, 165 Wn.2d 895, 214 P.3d 132 (2009).

Because the rules come from the courts rather than a statute, understanding how judges actually evaluate these agreements is essential. A prenup that looks solid on its face can still be thrown out if it fails the test the courts have laid down.

The Two-Prong Fairness Test

Under Matson, a Washington court analyzing a prenuptial agreement uses a two-prong analysis, and the spouse who wants to enforce the agreement carries the burden of proving it should stand.

The first prong asks whether the agreement is substantively fair, meaning whether it makes a fair and reasonable provision for the spouse who is not seeking to enforce it. If the agreement is substantively fair on its own terms, the analysis ends there and the agreement is enforceable. A court does not need to dig further when the deal itself is reasonable to both sides.

If the agreement is not substantively fair to the spouse resisting it, the court moves to the second prong, which examines the fairness of the process by which the agreement was made. Here the court asks two questions. First, did the spouses make a full disclosure of the amount, character, and value of the property involved? Second, was the agreement freely entered into on independent advice from counsel, with both spouses having full knowledge of their rights? If the process passes this test, then even an agreement that divides property in a lopsided way can be valid and binding. If the process fails, the agreement can be set aside.

This structure is why a prenup can be one-sided in its terms and still hold up, provided both people knew exactly what they were giving up and each had a genuine chance to get independent legal advice before signing. The fairness the law demands is either in the deal or in the way the deal was reached.

What a Prenup Cannot Do

A prenup is powerful, but it is not unlimited. It cannot dictate matters involving children. Decisions about child custody and child support are made based on the best interests of the child at the time the issue arises, and a couple cannot bargain those rights away in advance. A provision purporting to lock in custody or waive child support will not bind a court. It is also worth knowing that death-related community property arrangements between spouses are governed by their own separate rules and are a distinct topic from a divorce-focused prenup.

A Snohomish County Perspective

For couples in Snohomish County, a prenuptial agreement can bring real peace of mind, especially in second marriages, blended families, or situations where one partner owns a home or business. Because Washington's approach rests on case law rather than a checklist statute, the details of disclosure, timing, and independent counsel truly determine whether the agreement will survive a challenge. Getting those details right is the whole game.

A Thoughtful Way to Start a Marriage

A prenuptial agreement is simply a way for two people to make clear, informed decisions about their financial future before marriage, measured against Washington's community property rules and judged by the fairness standards the courts have built through cases like Matson and Bernard. Done well, it protects both spouses and reflects an honest partnership. The Law Office of Chad Foster helps couples across Snohomish County think through and prepare prenuptial agreements that are fair, fully disclosed, and built to hold up, and we would be glad to talk with you about yours.