You can sign a financial agreement after you are already married. Postnups are less common than prenups, but in the right situation they are one of the most powerful tools available in Massachusetts family law.
For decades, the question of whether postnuptial agreements were even enforceable in Massachusetts was unsettled. That changed in 2010, when the Supreme Judicial Court issued its decision in Ansin v. Craven-Ansin and formally recognized postnuptial agreements as a valid category of marital contract, subject to a careful set of safeguards.
What a postnup is
A postnuptial agreement is a contract between spouses, entered into during the marriage, that defines how property, assets, and certain financial issues will be handled if the marriage ends. It can address many of the same topics a prenup would, but it is signed at a different point in time, when the parties are already legally married.
The change in timing produces a meaningful change in the legal analysis. A spouse signing a prenup is choosing whether to enter the marriage. A spouse signing a postnup is already in the marriage and may be facing different pressures and dynamics. The court takes those differences seriously.
The five-factor enforceability test
In Ansin v. Craven-Ansin, the Supreme Judicial Court set out five factors that a postnuptial agreement must satisfy to be enforceable in Massachusetts:
- Each party had an opportunity to obtain separate legal counsel of their own choosing
- There was no fraud or coercion in obtaining the agreement
- All assets were fully and fairly disclosed before the agreement was signed
- Each party knowingly and explicitly agreed to waive marital rights
- The terms of the agreement were fair and reasonable both at the time of signing and at the time of enforcement
This test is more demanding than the prenuptial test. Both standards require fairness at the time of signing and at the time of enforcement, but the postnup analysis pays particular attention to the dynamics within an existing marriage. A spouse who signed under emotional pressure, or who lacked the practical ability to obtain independent counsel, has a stronger argument for invalidating the agreement than a similarly situated party to a prenup.
When postnups make sense
Postnuptial agreements are not for every couple. They serve specific purposes that come up in identifiable situations:
- After a near-divorce reconciliation, when both parties want to clarify the financial terms of continuing the marriage
- When one spouse launches or sells a business during the marriage and the parties want to address how it will be treated
- When one spouse receives a significant inheritance and wants to clarify whether and how it should be treated as marital property
- When a couple’s financial situation changes substantially and the parties want to put clearer expectations in writing
- When one spouse has discovered conduct that has created financial concerns short of divorce
In each of these situations, a postnup can do something that no other instrument can. It addresses financial issues without ending the marriage, and it does so on terms the parties shape themselves.
The bargaining-at-the-altar problem, solved at a different time
One of the practical advantages of a postnup over a prenup is the absence of wedding pressure. A prenup signed in the weeks leading up to a wedding can be challenged on the ground that one party had no real opportunity to walk away. A postnup signed years into a marriage carries no such timing pressure. Both parties have already committed to the marriage. The conversation is about how to structure the financial side of that commitment, not whether to proceed with it.
This is one reason that some couples who skipped a prenup before the wedding return to the same financial questions several years into the marriage. The questions did not go away. They simply moved to a different stage of life.
What a postnup can cover
The substantive scope of a postnup is similar to a prenup. It can address:
- Property division in the event of divorce
- The treatment of separate property and inheritances
- Alimony, including waivers, caps, or formulas
- The handling of business interests and other complex assets
- Estate-related provisions and inheritance rights
Like a prenup, a postnup cannot govern child custody, parenting time, or child support. Those issues remain subject to the best-interests standard at the time of any future divorce.
Independent counsel and full disclosure
For postnups, independent counsel is even more important than for prenups. The Ansin test makes clear that the opportunity for separate counsel is one of the five enforceability factors. A postnup signed without independent counsel for both parties is more vulnerable to challenge under the Ansin factors.
Full financial disclosure is equally critical. The disclosure must be complete enough that the signing party can make an informed decision. Understated business values, omitted accounts, or vague summaries of assets all undermine enforceability.
The relationship to legal separation
A postnup is sometimes confused with a separation agreement, but the two are different instruments. A separation agreement is filed with the court as part of a divorce or formal separation. A postnup is a private contract between spouses who remain married. The postnup can later inform a separation agreement if the marriage ends, but it does not by itself create any change in the marital status.
For couples considering whether to address financial issues now or proceed toward divorce, the choice between a postnup and a separation agreement is a significant fork in the road.
When a postnup is a relationship-saving tool
In some marriages, the act of negotiating a postnup is itself part of the work of repairing the relationship. A couple that has been through financial conflict, infidelity, or a near-divorce can find that putting clearer expectations in writing reduces the underlying tension. The agreement is not a substitute for the harder conversations, but it can give both parties the structure they need to commit to staying.
This is one of the situations where a postnup serves a function the prenup cannot. It is responsive to a specific moment in the marriage, not a generalized concern about the future.
If you are considering whether a postnuptial agreement could address your situation in Massachusetts, schedule a free consultation to discuss the specifics. These conversations tend to go more smoothly when they begin before a decision has been made about the marriage itself, rather than after.
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