Oregon Prenup Guide

Oregon Prenup Laws: Requirements & Enforceability

Everything engaged couples need to know about making a prenuptial agreement valid and enforceable in Oregon — in plain English, reviewed by attorney James Sexton, Esq.

Start Your Oregon Prenup →Last reviewed: July 2026

Key takeaways

  • Prenups are legal and enforceable in Oregon under the Uniform Premarital Agreement Act (ORS 108.700–108.740).
  • An Oregon prenup must be in writing and signed by both parties — no consideration, witnesses, or notarization are required by statute.
  • Spousal support can be limited or eliminated, but a court can override the waiver if it would push a spouse onto public or medical assistance (ORS 108.725).
  • A prenup fails if it was signed involuntarily, or was unconscionable and made without fair disclosure — and unconscionability is decided by the judge as a matter of law.
  • After the wedding, an Oregon prenup can only be amended or revoked by a written agreement signed by both spouses (ORS 108.720).

Are prenups legal in Oregon?

Yes — prenuptial agreements are legal and fully enforceable in Oregon under the state's Uniform Premarital Agreement Act.

Oregon adopted the Uniform Premarital Agreement Act at ORS 108.700 through 108.740. Under ORS 108.710, a premarital agreement must be in writing and signed by both parties, and it is enforceable without consideration. It becomes effective on marriage (ORS 108.715). Couples may contract about property rights, disposition of assets at separation or divorce, and the modification or elimination of spousal support — with the important public-assistance limit in ORS 108.725 described below.

What makes a prenup enforceable in Oregon?

An Oregon prenup is enforceable when it is written, signed, voluntary, and either conscionable or backed by fair financial disclosure — with the burden of proof on the spouse challenging it.

In writing and signed

ORS 108.710 requires a written agreement signed by both parties. Oregon does not require witnesses or notarization, and no consideration is needed.

Signed voluntarily

Under ORS 108.725, the challenger must prove the agreement was not executed voluntarily. An unrushed signing well before the wedding is the best protection.

Fair disclosure (or a valid waiver)

An agreement fails only if it was unconscionable when signed AND the challenging party received no fair and reasonable disclosure, did not waive disclosure in writing, and had no adequate knowledge of the other's finances.

Support waivers within limits

Support can be modified or eliminated, but if the waiver would make a spouse eligible for public assistance or medical assistance at separation or divorce, a court may order support to the extent needed to avoid that eligibility.

What you can & can't include

You can include

  • Defining separate vs. marital property for equitable distribution
  • How income and assets acquired during marriage are treated
  • Responsibility for premarital and marital debt
  • Modifying or eliminating spousal support (within ORS 108.725 limits)
  • Protecting a business, vineyard, or inheritance
  • Making a will or trust to carry out the agreement, and life insurance rights

You can't include

  • Anything that adversely affects a child's right to support
  • Child custody or parenting time
  • A support waiver that forces a spouse onto public or medical assistance
  • Terms that violate public policy or a criminal statute
  • Lifestyle clauses about personal behavior or duties

Oregon prenup quick facts

Governing statuteUniform Premarital Agreement Act — ORS 108.700–108.740
Property divisionEquitable distribution
NotarizationRecommended (not required by statute)
Waiting periodNone required — but sign well before the wedding
Spousal supportCan be waived, unless it forces public-assistance eligibility

See how Oregon's signing formalities compare in our prenup notarization requirements by state guide.

How Oregon courts evaluate enforcement

Oregon courts set aside prenups only when the challenger proves an involuntary signing, or unconscionable terms combined with a failure of financial disclosure.

ORS 108.725 places the burden on the spouse attacking the agreement and instructs that unconscionability is decided by the court as a matter of law, judged as of the time of signing. The statute's one built-in override is the public-assistance safety valve for support waivers. In practice, Oregon prenups fail for the familiar reasons — hidden assets, wedding-week pressure, lopsided terms — all of which are avoidable with full schedules, early signing, and reasonable provisions.

How to get a valid Oregon prenup for $599

Trusted Prenup creates a state-specific Oregon prenuptial agreement online — built to meet the requirements above and designed by James Sexton, Esq. A traditional attorney typically costs $2,500–$10,000; this is a flat $599.

1

Answer a few questions

A guided questionnaire captures your assets, debts, and wishes — most couples finish in under 90 minutes.

2

Generate your agreement

We assemble a complete prenup built to meet your state's exact legal requirements.

3

Review, sign & notarize

Review with your partner, then sign online with notarization handled for you.

Oregon note: Sign well before the wedding so no one can claim last-minute pressure.
Start Your Oregon Prenup →

Oregon prenup FAQ

How much does a prenup cost in Oregon?

An Oregon attorney-drafted prenup typically costs $2,000–$8,000+. Trusted Prenup creates a state-specific Oregon prenup online for a flat $599, with optional notarization and attorney-review add-ons.

Does an Oregon prenup need to be notarized?

No — ORS 108.710 requires only a written agreement signed by both parties, with no witnesses or notary. Notarization is still recommended to head off any later dispute about signatures, and it's available as an add-on.

Can a prenup be challenged in Oregon?

Yes, but the challenger bears the burden under ORS 108.725: they must prove the signing was involuntary, or that the agreement was unconscionable and made without fair disclosure, a written disclosure waiver, or adequate knowledge of the other's finances.

Can spousal support be waived in an Oregon prenup?

Yes — Oregon expressly allows couples to modify or eliminate spousal support. The limit: if the waiver would leave a spouse eligible for public assistance or medical assistance at separation or divorce, a court can order support despite the agreement.

Can we change or cancel an Oregon prenup after the wedding?

Yes — under ORS 108.720, a premarital agreement may be amended or revoked after marriage only by a written agreement signed by both spouses, and the change is enforceable without any new consideration.

Is Oregon a community property state?

No — Oregon uses equitable distribution, with a rebuttable presumption that both spouses contributed equally to property acquired during marriage. A prenup lets you replace that framework with rules you choose in advance.

Is an online prenup valid in Oregon?

Yes — Oregon enforces properly executed prenuptial agreements regardless of how they were drafted. What matters is execution: a written agreement, voluntary signatures, full financial disclosure, and Oregon's signing formalities. The full picture is in are online prenups legally binding.

More state prenup guides

Trusted Prenup is not a law firm and does not provide legal advice. This guide is general information about Oregon law and not a substitute for advice from a licensed attorney about your situation.