Postnuptial Agreement
Also known as: Postnup
A written contract between spouses, signed after the marriage, that defines what happens to property and support if the marriage ends.
A postnuptial agreement covers the same ground as a prenup but is signed during the marriage. Courts apply stricter scrutiny because married spouses owe each other a fiduciary duty — the disclosure and voluntariness requirements are higher.
Common triggers for postnups: a spouse starting a business after the wedding, a major inheritance, a couple deciding to reconcile finances after a dispute, or a couple that skipped a prenup before the wedding and wants to put one in place now.
Related terms
- Prenuptial Agreement — A written contract between two people who intend to marry that defines what happens to property, debt, and support if the marriage ends.
- Fiduciary Duty — A legal duty of utmost good faith and full disclosure owed by one party to another. Spouses owe each other a fiduciary duty; engaged couples generally do not.
- Financial Disclosure — The requirement that each spouse provides a complete and specific accounting of their finances — assets, debts, and income — before signing a prenup.
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