Prenups and postnups: what can you discuss?

A plain-language guide to the purposes of marital agreements, commonly discussed terms, and important legal limits in the United States.

Educational information only—not legal advice or a ready-to-sign agreement. Family law varies by state. Before signing, each partner should speak with their own family-law attorney in the relevant state.

Two different points in time

Prenup · before marriage

A premarital or prenuptial agreement is signed before the wedding. In Florida, for example, it takes effect upon marriage.

Postnup · after marriage

A postnuptial or marital agreement is made by spouses. New York, for example, permits agreements made before or during marriage. Formalities and enforcement rules can differ from prenups and across states.

Common prenup goals—not official legal “types”

One agreement can serve several purposes. These are conversation starters, not separate legal classifications.

Property and debt

Clarify what remains separate, how shared purchases are treated, and responsibility for particular obligations.

A business and its income

Address an existing business, ownership interests, growth in value, and income during marriage.

One spouse takes on more family care

Discuss financial security if a partner reduces paid work for the home or children—for example, savings, property, or possible spousal support.

Remarriage and estate planning

Coordinate the interests of spouses and children from earlier relationships with a will, trust, or life insurance.

When a postnup comes up

Circumstances may change after the wedding: a business, inheritance, child, income shift, or new division of roles. Spouses may want to revisit property and support expectations. A postnup does not automatically “fix” an older agreement; it must satisfy applicable law.

New rules for a business, property, or debts.
Financial security for a spouse who reduced paid work for the family.
Revisiting property expectations after an inheritance or major income change.

What agreements commonly address

•Rights in existing and future property, income, businesses, and debts.
•Division of property upon separation, divorce, or death.
•Spousal support, subject to important state-specific limits.
•Coordinated plans for wills, trusts, and life insurance.

What cannot be settled once and for all

•Parents cannot use a prenup to diminish a child’s right to support. Custody and parenting-time provisions do not replace review of the child’s best interests.
•Illegal or public-policy-violating terms may not be enforced. Do not treat personal expectations about housework or intimacy as guaranteed enforceable duties.
•Signatures alone do not guarantee enforcement: voluntariness, financial disclosure, fairness, and state-specific formalities matter.

An example is not a legal template

Our sample shows how a couple might write down expectations about housing, a family budget, and financial security. It does not automatically create an enforceable prenup or postnup.

View the fictional example (PDF)

How to use this guide

First, compare expectations and note where you agree or differ. If you want a legally effective agreement, take those notes to separate attorneys in the relevant state.

Start a conversation

Primary sources

Examples of state law and court guidance—not a survey of all 50 states.