Oregon
Oregon Prenuptial Agreement Laws: Requirements and Enforcement
Independently fact-checked against primary sources (last audited October 8, 2026). · 3 primary sources cited on this page. How we verify our legal content
Yes. Oregon enforces prenuptial agreements under its Uniform Premarital Agreement Act, ORS 108.700 to 108.740. An agreement must be in writing and signed by both parties (ORS 108.705), and ORS 108.725 sets out when a court will refuse to enforce one.
Information last verified on 2026-10-08. This article has not been reviewed by a licensed lawyer.
Jurisdiction scope: This article covers premarital agreements under Oregon's Uniform Premarital Agreement Act, ORS 108.700 to 108.740, with a note on property division under ORS 107.105. It does not cover Oregon case law on prenups, postnuptial agreements, which agreements the Act applies to by signing date, or other states' law. It is not a template and does not suggest terms.
Are prenups enforceable in Oregon?
Generally, yes. ORS 108.740(1) provides that "ORS 108.700 to 108.740 may be cited as the Uniform Premarital Agreement Act." Those sections set the formal requirements, list what can make an agreement unenforceable, and protect children's support.
The person resisting enforcement must prove one of the grounds in ORS 108.725, described below.
Formal requirements for an Oregon prenup
ORS 108.705 provides: "A premarital agreement must be in writing and signed by both parties. It is enforceable without consideration." Under ORS 108.715, the agreement becomes effective upon marriage. Oregon's general statute of frauds, ORS 41.580(1)(d), also requires an agreement made upon consideration of marriage, other than a mutual promise to marry, to be in writing and subscribed by the party to be charged.
ORS 108.705 does not mention notarization or witnesses. This page does not cover whether any other Oregon statute adds requirements for particular terms or property, such as real estate. A lawyer licensed in Oregon can review an agreement before it is signed.
When an Oregon prenup is not enforceable
ORS 108.725(1) sets out two grounds on which the party resisting enforcement can defeat the agreement.
Involuntary signing. Under ORS 108.725(1)(a), the agreement is not enforceable if the challenger proves "That party did not execute the agreement voluntarily."
Unconscionability plus lack of disclosure. Under ORS 108.725(1)(b), the challenger must prove that the agreement was unconscionable when it was signed and, before signing, that the challenger:
- was not given a fair and reasonable disclosure;
- did not voluntarily and expressly waive disclosure in writing; and
- did not have, or reasonably could not have had, adequate knowledge of the other party's property or obligations.
Unconscionability alone is not enough under this ground; the disclosure conditions must also be shown. ORS 108.725(3) adds: "An issue of whether a premarital agreement is unconscionable shall be decided by the court as a matter of law."
Counsel and timing. ORS 108.725 does not list independent legal counsel or a waiting period before the wedding as a condition of enforcement. This page does not cover how Oregon courts weigh those facts when deciding voluntariness or unconscionability.
Spousal support waivers in Oregon
A prenup can modify or eliminate spousal support, but ORS 108.725(2) sets a limit. If that change would make a party eligible for public assistance or medical assistance at the time of separation or dissolution, "a court, notwithstanding the terms of the agreement, may require the other party to provide support to the extent necessary to avoid that eligibility."
For how Oregon courts set spousal support without an agreement, see Oregon alimony laws.
What an Oregon prenup cannot do
ORS 108.710(2) provides: "The right of a child to support may not be adversely affected by a premarital agreement."
The Act sections cited here do not address child custody or parenting time, which the court decides when the marriage ends under ORS 107.105(1).
If the marriage turns out to be void
Under ORS 108.730, "If a marriage is determined to be void, an agreement that would otherwise have been a premarital agreement is enforceable only to the extent necessary to avoid an inequitable result."
Changing or cancelling a prenup after the wedding
ORS 108.720 provides: "After marriage, a premarital agreement may be amended or revoked only by a written agreement signed by the parties." The amendment or revocation is enforceable without consideration.
Time limits on prenup claims
ORS 108.735 provides: "Any statute of limitations applicable to an action asserting a claim for relief under a premarital agreement is tolled during the marriage of the parties to the agreement." The same section keeps the equitable defenses of laches and estoppel available, so delay can still matter.
Postnuptial agreements in Oregon
ORS 108.700 to 108.740 address premarital agreements, signed before marriage. This page does not cover how Oregon treats agreements spouses sign after the wedding, other than amendments to a premarital agreement under ORS 108.720. Ask an Oregon lawyer about a postnuptial agreement.
Oregon property division without a prenup
Without an agreement, the court divides property "as may be just and proper in all the circumstances" under ORS 107.105(1)(f), with a rebuttable presumption that both spouses contributed equally to property acquired during the marriage; property received by gift or inheritance and held separately is excluded from that presumption. See Oregon divorce laws.
Disclaimer: This article provides general legal information about premarital agreements under Oregon's Uniform Premarital Agreement Act, ORS 108.700 to 108.740. It is not legal advice and is not a template. The information was verified on 2026-10-08, and the law can change. For advice about a specific agreement, consult a lawyer licensed in Oregon.
Related
- Prenuptial agreement laws in every state
- Oregon divorce laws
- Oregon alimony laws
- Oregon child support laws
Last updated: 2026-10-08.
Frequently Asked Questions
Does a prenup have to be notarized in Oregon?
ORS 108.705 requires a premarital agreement to be in writing and signed by both parties, and it does not mention notarization or witnesses.
How can a prenup be thrown out in Oregon?
Under ORS 108.725(1), the challenger must prove they did not sign voluntarily, or that the agreement was unconscionable when signed and they lacked fair disclosure, a written waiver of disclosure and adequate knowledge of the other party's property or obligations.
Do both people need a lawyer for a prenup in Oregon?
ORS 108.725 does not list independent counsel as a condition of enforcement. Either party may still choose to have an Oregon lawyer review the agreement.
Can a prenup waive alimony in Oregon?
It can modify or eliminate spousal support, but under ORS 108.725(2) a court may still order support to keep a spouse from becoming eligible for public or medical assistance.
Can a prenup decide child support in Oregon?
No. ORS 108.710(2) provides that a premarital agreement may not adversely affect a child's right to support.
Can you change a prenup after marriage in Oregon?
Yes, but only by a written agreement signed by both spouses (ORS 108.720).
Updates
Independently fact-checked against the cited primary sources
The Law Behind This Article
This article rests on the statutory provisions below, held in our own legal record and retrieved from the official source. Tap a section to read the operative text.
Oregon Revised Statutes, Chapter 108
§ 108.705Agreement to be in writing; consideration not requiredIn force
A premarital agreement must be in writing and signed by both parties. It is enforceable without consideration. [1987 c.715 §2] Note: See note under 108.700.
Official text (excerpt) · last checked 2026-07-29 · Read the full text in our law library · Verify at oregonlegislature.gov
§ 108.710Subjects of agreement; child support not to be adversely affectedIn force
(1) Parties to a premarital agreement may contract with respect to: (a) The rights and obligations of each of the parties in any of the property of either or both of them whenever and wherever acquired or located; (b) The right to buy, sell, use, transfer, exchange, abandon, lease, consume, expend, assign, create a security interest in, mortgage, encumber, dispose of or otherwise manage and control property; (c) The disposition of property upon separation, marital dissolution, death or the occurrence or nonoccurrence of any other event; (d) The modification or elimination of spousal support; (e) The making of a will, trust or other arrangement to carry out the provisions of the agreement; (f) The ownership rights in and disposition of the death benefit from a life insurance policy; (g) The choice of law governing the construction of the agreement; and (h) Any other matter, including their personal rights and obligations, not in violation of public policy or a statute imposing a criminal penalty. (2) The right of a child to support may not be adversely affected by a premarital agreement. [1987 c.715 §3] Note: See note under 108.700.
Official text (excerpt) · last checked 2026-07-29 · Read the full text in our law library · Verify at oregonlegislature.gov
§ 108.720Modification of agreement; consideration not requiredIn force
After marriage, a premarital agreement may be amended or revoked only by a written agreement signed by the parties. The amended agreement or the revocation is enforceable without consideration. [1987 c.715 §5] Note: See note under 108.700. 108.725 Party may prove agreement unenforceable; when court may require support; determination of unconscionability. (1) A premarital agreement is not enforceable if the party against whom enforcement is sought proves that: (a) That party did not execute the agreement voluntarily; or (b) The agreement was unconscionable when it was executed and, before execution of the agreement, that party: (A) Was not provided a fair and reasonable disclosure of the property or financial obligations of the other party; (B) Did not voluntarily and expressly waive, in writing, any right to disclosure of the property or financial obligations of the other party beyond the disclosure provided; and (C) Did not have, or reasonably could not have had, an adequate knowledge of the property or financial obligations of the other party.
Official text (excerpt) · last checked 2026-07-29 · Read the full text in our law library · Verify at oregonlegislature.gov
§ 108.735Statute of limitations; defensesIn force
Any statute of limitations applicable to an action asserting a claim for relief under a premarital agreement is tolled during the marriage of the parties to the agreement. However, equitable defenses limiting the time for enforcement, including laches and estoppel, are available to either party. [1987 c.715 §8] Note: See note under 108.700. 108.740 Short title; construction; severability. (1) ORS 108.700 to 108.740 may be cited as the Uniform Premarital Agreement Act. (2) ORS 108.700 to 108.740 shall be applied and construed to effectuate its general purpose to make uniform the law with respect to the subject of this Act among states enacting it. (3) If any provision of ORS 108.700 to 108.740 or its application to any person or circumstance is held invalid, the invalidity does not affect other provisions or applications of ORS 108.700 to 108.740 which can be given effect without the invalid provision or application, and to this end the provisions of ORS 108.700 to 108.740 are severable. [1987 c.715 §9] Note: See note under 108.700. _______________
Official text (excerpt) · last checked 2026-07-29 · Read the full text in our law library · Verify at oregonlegislature.gov
§ 108.700Definitions for ORS 108.700 to 108.740In force
As used in ORS 108.700 to 108.740: (1) “Premarital agreement” means an agreement between prospective spouses made in contemplation of marriage and to be effective upon marriage. (2) “Property” means an interest, present or future, legal or equitable, vested or contingent, in real or personal property, including income and earnings. [1987 c.715 §1] Note: 108.700 to 108.740 were enacted into law by the Legislative Assembly but were not added to or made a part of ORS chapter 108 or any series therein by legislative action. See Preface to Oregon Revised Statutes for further explanation.
Official text (excerpt) · last checked 2026-07-29 · Read the full text in our law library · Verify at oregonlegislature.gov
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Sources and References
- Oregon Revised Statutes chapter 108, Uniform Premarital Agreement Act sections (ORS 108.700, 108.705, 108.710, 108.715, 108.720, 108.725, 108.730, 108.735, 108.740)(oregonlegislature.gov).gov
- Oregon Revised Statutes chapter 41 (ORS 41.580, statute of frauds)(oregonlegislature.gov).gov
- Oregon Revised Statutes chapter 107 (ORS 107.105, property division and judgment provisions)(oregonlegislature.gov).gov