Massachusetts Prenuptial Agreement Laws: Enforceability Rules (2026)

A prenuptial agreement can be enforced in Massachusetts. The statute, General Laws chapter 209, section 25, allows a written contract before marriage about property, and the Supreme Judicial Court has set the tests a court applies before enforcing one at divorce, most fully in DeMatteo v. DeMatteo, 436 Mass. 18 (2002).

Information last verified on 2026-10-08. This article has not been reviewed by a licensed lawyer.

Jurisdiction scope: This article covers premarital (antenuptial) and marital agreements under Massachusetts law: G.L. c. 209 ss. 25 and 26, the property-division statute G.L. c. 208 s. 34, and the Supreme Judicial Court decisions in DeMatteo v. DeMatteo (2002) and Ansin v. Craven-Ansin (2010), including the earlier cases DeMatteo quotes. It does not cover inheritance or elective-share waivers, tax issues, or the law of any other state.

What Law Governs Prenups in Massachusetts

Massachusetts prenup law has two parts. A statute, G.L. c. 209 s. 25, authorizes the premarital property contract, and section 26 adds a recording rule. The rules courts use to decide whether to enforce an agreement at divorce come from decisions of the Supreme Judicial Court.

Section 25 says:

"At any time before marriage, the parties may make a written contract providing that, after the marriage is solemnized, the whole or any designated part of the real or personal property or any right of action ... shall remain or become the property of the husband or wife, according to the terms of the contract." G.L. c. 209 s. 25

In DeMatteo, the SJC discussed the Uniform Premarital Agreement Act as a model, not as Massachusetts law, and described Massachusetts's own "fair and reasonable" approach as "consonant with the standard recognized in a number of other States." The Massachusetts chapters cited here contain no enactment of that uniform act; this page does not take a position on the point beyond that.

Formal Requirements

A Massachusetts prenup must be in writing and made before the marriage (c. 209 s. 25). Sections 25 and 26 also call for a schedule of the property, described clearly enough for a creditor to tell it apart, to be annexed to the contract and recorded in the registry of deeds before the marriage or within 90 days after it.

Section 26 sets the consequence of not recording:

"If the contract is not so recorded, it shall be void except as between the parties thereto and their heirs and personal representatives." G.L. c. 209 s. 26

That language preserves the contract between the spouses themselves. This page does not cover whether the recording rule matters for an agreement that only governs what happens at divorce.

Sections 25 and 26 contain no notarization or witness requirement. The SJC has said the agreement must also follow ordinary contract law:

"An antenuptial agreement must also, of course, comport with the rules governing the formation of all contracts, for example, the necessity of consideration and the absence of fraud, misrepresentation, and duress." DeMatteo v. DeMatteo, 436 Mass. 18 (2002)

When a Massachusetts Court Will Enforce a Prenup

Massachusetts courts apply a two-step test, which the SJC restated in DeMatteo:

"First, a judge must determine whether an antenuptial agreement is valid. Second, 'the agreement must be fair and reasonable at the time of entry of the judgment nisi.'" DeMatteo, 436 Mass. at 26-27, quoting Osborne v. Osborne, 384 Mass. 591, 599 (1981)

The second step means the agreement is looked at twice: once as of the day it was signed and again when the divorce judgment is entered.

Step One: Validity at Signing

For the first step, the SJC applies the rules from Rosenberg v. Lipnick, 377 Mass. 666, 672 (1979), as quoted in DeMatteo. The court asks whether the agreement:

"(1) . . . contains a fair and reasonable provision as measured at the time of its execution for the party contesting the agreement; (2) the contesting party was fully informed of the other party's worth prior to the agreement's execution, or had, or should have had, independent knowledge of the other party's worth; and (3) a waiver by the contesting party is set forth"

Separately, the general contract rules above (consideration, no fraud, misrepresentation or duress) apply. This page does not cover any rule requiring each party to have a separate lawyer before signing a prenup, or any required waiting period between presenting and signing one. Those are gaps in what this page covers, not findings that such rules never matter; a lawyer licensed in Massachusetts can explain how courts weigh them.

Step Two: Fair and Reasonable at Divorce

At the second step, the court looks at the agreement again as of the entry of the judgment nisi in the divorce, the point at which the divorce judgment is entered.

The SJC has said this second look is narrow. In DeMatteo, it held that a judge may not relieve the parties from a valid agreement unless, "due to circumstances occurring during the course of the marriage, enforcement of the agreement would leave the contesting spouse 'without sufficient property, maintenance, or appropriate employment to support' herself." The examples it gave are the unanticipated mental or physical deterioration of the contesting spouse, or inflation eroding agreed support payments so far as to nullify what the parties intended. The SJC applied the same standard in Austin v. Austin, 445 Mass. 601 (2005).

In DeMatteo itself, the SJC held that "the evidence did not warrant a conclusion that the antenuptial agreement is unenforceable" and reversed the Probate and Family Court's refusal to enforce it.

Limits on What a Prenup Can Do

The SJC, quoting Osborne, has identified situations where a court may deviate from the terms of an agreement:

"in certain situations, for example, where it is determined that one spouse is or will become a public charge, or where a provision affecting the right of custody of a minor child is not in the best interests of the child." DeMatteo, quoting Osborne, 384 Mass. 591

Two points follow from that passage:

• Spousal support waivers: an agreement that would leave a spouse a public charge is one the court may modify.
• Children: a custody provision that is not in the child's best interests may be modified. In DeMatteo itself, the agreement left custody and child support to the court.

This page does not cover other limits on child support terms.

Changing or Revoking a Prenup

Sections 25 and 26 do not address amending or revoking a premarital agreement, and this page does not cover the question. For agreements spouses make after the wedding, see the next section.

Postnuptial Agreements in Massachusetts

Massachusetts courts can enforce agreements spouses make during the marriage. In Ansin v. Craven-Ansin, 457 Mass. 283 (2010), the SJC held:

"Enforcement of a marital agreement is not contrary to public policy." Ansin v. Craven-Ansin, 457 Mass. 283 (2010)

Under "careful scrutiny," the judge must determine at a minimum whether each spouse had an opportunity to obtain separate legal counsel, whether there was fraud or coercion, whether all assets were fully disclosed, whether each spouse knowingly agreed in writing to waive the right to a judicial equitable division of assets, and whether the terms were fair and reasonable both when signed and at divorce. The spouse seeking enforcement bears the burden. Actual representation by separate counsel is not required.

How Property Is Divided Without a Prenup

Without an enforceable agreement, Massachusetts divides property by equitable distribution: under G.L. c. 208 s. 34 the court "may assign to either husband or wife all or any part of the estate of the other." For property division and the divorce process, see Massachusetts divorce laws. For spousal support, see Massachusetts alimony laws.

A prenup is a contract between two people with different interests. A lawyer licensed in Massachusetts can draft or review these agreements, and this page does not offer sample terms.

Disclaimer: This article provides general legal information about premarital and marital agreements under Massachusetts law (G.L. c. 209 ss. 25 and 26 and Supreme Judicial Court decisions), verified on 2026-10-08. It is not legal advice. For advice about your situation, consult a lawyer licensed in Massachusetts or the self-help resources of the Massachusetts Probate and Family Court.

Related

• Prenuptial agreement laws in every state
• Massachusetts divorce laws
• Massachusetts alimony laws

Last updated: 2026-10-08.

Frequently Asked Questions

Are prenups enforceable in Massachusetts?

Yes, if they pass the SJC's two-step test: valid when signed under the Rosenberg rules, and fair and reasonable at the entry of the judgment nisi (DeMatteo v. DeMatteo, 2002). At divorce, a valid agreement is enforced unless circumstances arising during the marriage would leave the contesting spouse without sufficient property, maintenance, or appropriate employment.

Does a prenup have to be notarized in Massachusetts?

G.L. c. 209 ss. 25 and 26 contain no notarization or witness requirement. The agreement must be in writing, made before the marriage, and meet ordinary contract rules.

Does a Massachusetts prenup have to be recorded?

Under G.L. c. 209 s. 26, an unrecorded section 25 contract is void except between the parties and their heirs and personal representatives. Whether that matters for a divorce-only agreement is unsettled in the sources reviewed.

What makes a prenup invalid in Massachusetts?

A court may find an agreement invalid if it fails the Rosenberg rules on fair provision, disclosure of worth and a stated waiver, or ordinary contract rules such as fraud or duress (DeMatteo, 2002).

Can a prenup decide child custody in Massachusetts?

A court may modify a custody provision that is not in the child's best interests (Osborne, as quoted in DeMatteo).

Are postnuptial agreements valid in Massachusetts?

Yes. In Ansin v. Craven-Ansin (2010) the SJC held that enforcing a marital agreement is not contrary to public policy, subject to criteria including an opportunity to obtain separate counsel, full disclosure and fairness.