California Postnuptial Agreements (Post-Nups)

It is a common misconception that in California, a prenuptial (prenup) agreement is the same as a postnuptial agreement but they are not. In California, there is a presumption that a prenuptial agreement is valid. The converse is true with a postnuptial agreement (postnup). There is a presumption that postnups are invalid.

A postnuptial agreement is drafted after a couple is already married. Postnups are drafted for a variety of reasons, even when the marriage is doing just fine. A postnuptial agreement can be used to truly define assets like each spouse’s respective separate property, financial responsibilities, or rights to the family business. Sometimes a postnup is drafted because the couple simply did not have enough time before they got married. (See discussion of premarital agreements, or “prenups”.)

Why might you need a postnuptial agreement?

A California postnuptial agreement can outline a variety of things:

  • Spousal Support Terms
  • Respective interest in the family residence
  • How property is to be characterized
  • Responsibility for debs, liabilities, and loans.
  • Insurance beneficiaries
  • Family Pets
  • Division of property upon death
What are the requirements for a postnuptial agreement?

To establish the validity of a postnuptial agreement, the agreement must:

  • Be in writing
  • It must be signed and notarized by both spouses
  • Be voluntary.  The agreement may not force the other spouse to sign the agreement.
  • Be equitable.  If a postnup is too “one-sided” it can be deemed invalid due to its unconscionability.
  • Contain full disclosure.  This can be a tedious and cumbersome process, especially when a couple is already married.
What about spousal support?

California courts are very cautious to validate postnuptial agreements which waive or limit post-divorce spousal support.  A postnuptial agreement which attempts to contract in or out of child support is not enforceable.

Get your own attorney

If receive a postnuptial agreement for your signature, it is highly advised that you seek an independent counsel to conduct a review.  The preparer of the agreement is not your attorney, and they cannot give you advice as to any rights you may be waived under the agreement.  Further, if only one party was represented by an attorney, the Courts have an additional reason to scrutinize the validity of the document.

Do not sign until you know what you are signing.  Some mistakes cannot be fixed.

Christina Weed  CBLS Tax Law


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Mendes Weed, LLP offices are located in Walnut Creek and our skilled attorneys provide family, tax, business, and trust law assistance for clients. For your convenience, we also have attorneys' offices in San Francisco and Sacramento by appointment only.

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