Postnuptial agreement

A postnuptial agreement (commonly called a "postnup") is a legally binding contract signed by two people after they are already married that outlines how assets, debts, income, and other financial matters will be divided in the event of divorce, separation, or death. Postnups serve the same fundamental purpose as prenups but are created during an existing marriage rather than before the wedding.

29 steps across 11 sections

1. Reconciliation After Marital Difficulties

  • One of the most common triggers — a couple working through infidelity, separation, or trust issues may use a postnup to set new financial expectations and provide a sense of security as they rebuil...
  • A postnup can formalize commitments made during counseling or mediation

2. Inheritance or Windfall

  • When one spouse receives a significant inheritance, gift, or lottery winnings, a postnup can clarify that these assets remain separate property
  • Protects the inherited assets from commingling disputes in a future divorce

3. Starting or Growing a Business

  • If one spouse starts a business during the marriage, a postnup can define how the business and its appreciation will be treated in a divorce
  • Protects the business from being divided or forced to sell

4. Career Change or Stay-at-Home Parent

  • When one spouse leaves the workforce to raise children or support the other's career, a postnup can ensure fair compensation for that sacrifice
  • Can establish spousal support terms that reflect the career sacrifice

5. Significant Change in Financial Circumstances

  • Major salary increase, stock options, real estate acquisition, or taking on significant debt
  • Protects both parties by clarifying ownership and responsibility as the financial picture changes

6. Blended Family Considerations

  • Ensuring children from a prior marriage are protected
  • Coordinating the postnup with estate planning documents (trusts, wills, beneficiary designations)

7. Missed Prenup

  • Many couples who wanted a prenup but ran out of time or could not agree on terms before the wedding use a postnup to achieve the same goals

8. Protecting Against a Spouse's Debts

  • If one spouse takes on risky business debt or has creditor issues, a postnup can shield the other spouse's assets

9. General Requirements (Similar to Prenups)

  • Written agreement — must be in writing and signed by both spouses
  • Voluntary — both parties must enter freely, without duress or coercion
  • Full financial disclosure — both spouses must provide complete, honest disclosure of assets, debts, and income
  • Fair and reasonable terms — cannot be unconscionable or grossly one-sided
  • Independent legal counsel — each spouse should have their own attorney (strongly recommended; required in some states)

10. Stricter Scrutiny for Postnups

  • Spouses already owe each other fiduciary-like duties of good faith and fair dealing
  • Power imbalances within a marriage (financial dependence, emotional leverage) are harder to detect than between engaged individuals
  • One spouse may feel pressured to sign to "save the marriage" or avoid conflict
  • Courts want to ensure that neither spouse exploited the marital relationship to gain an unfair advantage

11. What Can Void a Postnup

  • Duress or coercion — one spouse pressured or threatened the other into signing
  • Fraud or misrepresentation — false financial information was provided
  • Unconscionability — terms are grossly unfair to one party
  • No independent counsel — especially problematic if one party had an attorney and the other did not
  • Lack of financial disclosure — hidden assets or debts
  • Child custody or support provisions — courts will not enforce provisions attempting to predetermine child custody or set child support

Common Mistakes

  • Using the same attorney
  • Incomplete financial disclosure
  • Signing under pressure
  • Including child custody or support terms
  • Making it grossly one-sided

Pro Tips

  • Frame it as financial planning, not a threat
  • Consider a mediator
  • Time it well
  • Be comprehensive in financial disclosure
  • Include a review clause

Sources

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