Postnuptial Agreements in Minnesota

Last reviewed November 3, 2026

A postnuptial agreement in Minnesota is a written contract between spouses, made after the wedding, that settles how property, maintenance, and estate rights will be handled if the marriage ends. Minnesota law permits these agreements, but it holds them to a stricter standard than agreements signed before marriage. Under Minn. Stat. § 519.11, subd. 1d, a postnuptial agreement must satisfy every fairness requirement for an antenuptial agreement and two additional safeguards. This page explains those requirements and the situations in which postnuptial agreements are most often used. It is part of the site’s guide to antenuptial and postnuptial agreements.

Why the Law Treats Postnuptial Agreements Differently

Before marriage, each person can decline to marry if the terms are unacceptable. After marriage, that leverage is different. Spouses already share a household, finances, and often children. They also owe each other duties that strangers do not. For these reasons, the Legislature added protections that apply only once the parties are married.

The Requirements for a Valid Postnuptial Agreement

Everything Required of an Antenuptial Agreement

A postnuptial agreement must comply with the procedural and substantive fairness rules for antenuptial agreements (§ 519.11, subd. 1d(a)). These include:

• full and fair disclosure of each spouse’s income and property, which cannot be waived;
• a meaningful opportunity to consult independent counsel;
• a written agreement signed before two witnesses and acknowledged before a notary or other officer;
• voluntary execution, free of duress; and
• terms that are not unconscionable, either when signed or because of drastically changed circumstances.

The seven-days-before-the-wedding rule naturally does not apply. Each of the other requirements is explained on the site’s antenuptial agreements page.

Separate Counsel for Each Spouse

This is the most significant difference. A postnuptial agreement is valid and enforceable only if each spouse is represented by separate legal counsel when it is signed (§ 519.11, subd. 1d(c)). For an antenuptial agreement, an opportunity to consult counsel is enough. For a postnuptial agreement, however, actual representation is mandatory. An agreement signed without it is not merely open to challenge. Under the statute, it is not valid.

The Two-Year Presumption

A postnuptial agreement is presumed unenforceable if either spouse starts a legal separation or dissolution within two years after signing it (§ 519.11, subd. 1d(d)). The spouse seeking to enforce it can overcome that presumption only by proving that the agreement is fair and equitable.

This rule discourages using a postnuptial agreement as a prelude to an already-planned divorce. In practice, an agreement is most secure when the marriage continues well beyond two years after it is signed.

What a Postnuptial Agreement May Cover

A conforming postnuptial agreement may decide any matter that an antenuptial agreement may decide (§ 519.11, subd. 1d(b)). That includes:

• the classification and division of marital and nonmarital property, as defined in Minn. Stat. § 518.003, subd. 3b;
• spousal maintenance; and
• each spouse’s rights in the other’s estate.

As with antenuptial agreements, child custody, parenting time, and child support remain subject to the court’s determination when a case arises.

Common Reasons Spouses Use Them

Postnuptial agreements serve a range of legitimate purposes. Typical examples include:

• Amending an existing prenuptial agreement. After marriage, an antenuptial agreement may be changed or revoked only by a valid postnuptial agreement (§ 519.11, subd. 2a).
• Protecting a new business or inheritance. A spouse may receive an inheritance or start a company during the marriage and want its status clarified.
• Addressing a major financial change. A significant increase in income, a move, or one spouse leaving the workforce may prompt new terms.
• Clarifying commingled assets. When nonmarital funds have been mixed with marital funds, an agreement can document how they should be treated, before tracing becomes difficult.
• Estate planning. Spouses with children from earlier relationships may use an agreement to coordinate inheritance rights.

What Is Not a Postnuptial Agreement

The statute excludes some arrangements from its definition (§ 519.11, subd. 1d(e)). Agreements and waivers of elective-share and similar probate rights under Minn. Stat. §§ 524.2-201 to 524.2-215 keep their own validity rules. Likewise, a conveyance permitted by Minn. Stat. § 500.19, such as a transfer of real estate between spouses, is not treated as a postnuptial agreement.

A marital termination agreement, signed as part of a pending divorce, is also different. It is a settlement approved by the court within the case, not a postnuptial agreement intended to govern a continuing marriage.

Agreements Signed Before August 1, 2024

The current requirements apply to agreements executed on or after August 1, 2024 (§ 519.11, subd. 6). Earlier postnuptial agreements are evaluated under the version of § 519.11 in effect when they were signed. That earlier version likewise required separate counsel and contained a two-year presumption. Its other conditions, however, differed in several respects. An older agreement should be reviewed under the law that applied at the time.

Practical Considerations

1. Each spouse retains a separate attorney. This is a legal requirement, not a recommendation.
2. Disclose completely. Exchange written schedules of income, assets, and debts with the basis for each value.
3. Allow time for review. Avoid signing under deadline pressure, such as during a financial crisis or marital conflict.
4. Observe the formalities. Sign before two witnesses and a notary.
5. Coordinate with estate documents. Update wills, trusts, and beneficiary designations to match the agreement.

Without an agreement, a court divides marital property under Minn. Stat. § 518.58 and decides maintenance under § 518.552. For those default rules, see Minnesota Spousal Maintenance and House in a Divorce.