Wyoming Prenuptial Agreement
Wyoming prenups are governed entirely by case law — no UPAA, no prenup-specific statute (only Wyo. Stat. § 1-23-105(a)(iii) requiring a writing). Lund v. Lund (1993) requires courts to enforce prenups or state a "cogent rationale" for refusing. Dual review hasn't been precluded, but no Wyoming case has used it to strike a prenup. Spousal support waivers are fully enforceable (Seherr-Thoss, 2006); no alimony floor, hardship exception, or durational ceiling exists.
Bottom line: Wyoming earns a B grade. Strong pro-enforcement defaults and the most permissive alimony-waiver framework in the country, but the absence of a statute and limited case law (8 Supreme Court decisions in 45 years) leave more uncertainty than codified UPAA states.
Wyoming Prenup Enforceability Rating: B
Wyoming Prenup Laws: Key Statutes Explained
Wyoming Common Law (1979–present); Wyo. Stat. § 1-23-105(a)(iii)
No prenup-specific statute. Wyoming has not adopted UPAA or UPMAA. Enforcement governed by contract case law: Laird (1979), Lund (1993), Seherr-Thoss (2006), Morrison (2024).
Separate Property
All assets can remain separate property, avoiding costly divorce settlements. Joint assets and debts titled in both names can be split 50/50 according to a prenuptial agreement. Address commingling expressly — Wyoming courts will not write in missing terms (Morrison, 2024).
Same Construction as Other Contracts (Pro-Prenup)
Wyoming construes prenups under ordinary contract rules — no heightened fairness review, no implied terms. Trial courts must enforce the agreement or state a "cogent rationale" on the record for refusing (Lund, 1993).
Enforcement Standard — Common-Law Two-Prong Test
A prenup is unenforceable only if the challenger proves: (1) involuntary execution by fraud, duress, or denial of opportunity to read; OR (2) unconscionability under general contract doctrine. Failure to read is not a defense for a competent adult (Laird, 1979).
Spousal Support Waivers Enforceable
Wyoming enforces full spousal-support waivers; no durational ceiling, public-assistance floor, or hardship carve-out (Seherr-Thoss, 2006). Partial breach is remedied with damages, not rescission.
Timing
No minimum specified, but we recommend signing the prenup 60+ days before the wedding, with both parties having 2-3 weeks to review the final version to minimize challenge risk. Reach out to an attorney at least 4-6 months before the wedding with your draft prenup. Better yet, sign the prenup before proposing.
Independent Counsel
Not required (Seherr-Thoss, 2006), but separate counsel dramatically strengthens enforceability if the agreement is later challenged. Forecloses the most common attack vector: voluntariness.
Financial Disclosure
No statutory standard. Cases turn on whether the challenger had meaningful access to information about the other's wealth (Laird). Attach detailed schedules with appraised values. PerfectPrenup includes both schedules and waiver language.
Moderate Burden to Challenge
Challenger must prove involuntariness or unconscionability by preponderance of evidence. Wyoming courts "favor" enforcement (Lund) and will not rewrite a poor bargain (Morrison), but no statute bars second-look review — draft for both execution-time and enforcement-time fairness.
Child Support and Custody
Child support and custody clauses are unenforceable and could undermine the entire agreement. Do not include.
Wyoming Prenuptial Agreement Court Cases
Combs v. Sherry-Combs, 865 P.2d 50 (Wyo. 1993)
A "Three-Year Renewable Marriage Contract" signed approximately one month after the wedding was held not to be a prenuptial agreement and was unenforceable as a postnuptial agreement for lack of separate consideration, with its custody and divorce-by-termination provisions also void as against public policy.
Bradley v. Bradley, 118 P.3d 984 (Wyo. 2005)
The Wyoming Supreme Court reversed a default divorce decree that had enforced a prenup and its adultery-forfeiture amendment (originally requiring husband to pay wife $100,000 plus $10,000/month for two years) because wife was denied due process when neither the prenup, the amendment, nor the proposed decree was served on her.
Bradley v. Bradley, 164 P.3d 117 (Wyo. 2007)
On remand, a postmarital amendment to the same prenup was held unenforceable because the prenup's Minnesota choice-of-law clause governed amendments, and the amendment failed Minnesota's statutory formalities (two witnesses or notary).
Laird v. Laird, 597 P.2d 463 (Wyo. 1979)
Foundational Wyoming case enforcing a prenup against a husband who claimed he signed without reading and was misled about its scope, holding that prenups are governed by the same rules of construction as other contracts and that a competent party's failure to read does not invalidate a contract absent fraud, duress, or denial of opportunity to read.
Lund v. Lund, 849 P.2d 731 (Wyo. 1993)
Reversing a trial court that had ignored an antenuptial agreement and its $1 million amendment to award only $300,000, the Wyoming Supreme Court held that trial courts must enforce antenuptial agreements unless the record contains a "cogent rationale" for refusing to do so.
Barton v. Barton, 996 P.2d 1 (Wyo. 2000)
Affirmed application of a 1986 prenup that retained each spouse's separate property but permitted gifts, holding that a 31-acre parcel husband purchased with inherited funds but titled in wife's name was presumed gifted to her under the prenup's gift exception, with the presumption unrebutted on the record.
Seherr-Thoss v. Seherr-Thoss, 141 P.3d 705 (Wyo. 2006)
Enforced a prenup's spousal-support waiver and separate-property provisions despite husband's complete failure to make the contractually required $10,000 annual payments to wife, holding that partial breach does not void a prenup, independent counsel is not required, and the gift presumption arising from joint titling can be rebutted.
Morrison v. Hinson-Morrison, 555 P.3d 944 (Wyo. 2024)
After a 15-year marriage during which husband formed three oil and gas companies and made substantial financial contributions to wife's separately-held businesses and properties, the court enforced the prenup as written and treated those contributions as spousal gifts, refusing to read in a commingling-reimbursement provision the parties had not drafted.
5-Step Checklist: How to Sign & Execute a Prenup in Wyoming
Step 1: Download and read the Wyoming prenuptial agreement
Start with our free template. It is written for Wyoming-specific case law (Laird, Lund, Seherr-Thoss, Morrison) and Wyo. Stat. § 1-23-105(a)(iii). Wyoming has not adopted the UPAA, so prenups are governed by contract common law. Read it in full — know what you are getting into legally with marriage. The 15+ pages is written thoroughly to include rebuttals to common legal challenges and fallback provisions.
Step 2: Draft changes on your own
See a clause you don't like? Copy it into an AI like Claude, explain what you'd like to change or what you want the clause "to do." Save any changes as a separate alternate version — don't overwrite the original. Bring both versions to your attorney review. Note: AI is often gender-biased and crafts terms beyond what is legally required. Push back on its output.
Step 3: Find a matrimonial or divorce lawyer in Wyoming
Find a matrimonial or divorce attorney in your state. Avvo, Findlaw, and Justia are good. Look for someone with 10+ years experience. Call or email and ask them how much to review your draft prenup and help with signing. Send them your draft.
Step 4: Meet your lawyer 4–6 months before the wedding
Our recommendation: sign the prenup before proposing. That way, you both get the legal work out of the way, and you know this is the right person to marry. Already proposed? 4–6 months before the wedding should leave you enough time to give your spouse 1–2 weeks to review the final draft and have it signed 60+ days before the wedding. Wyoming has no minimum waiting period, but Combs (1993) invalidated a document signed roughly a month after the wedding as a postnup for lack of consideration — sign before the ceremony, with margin.
Step 5: Review and sign the prenup with your attorney
Wyoming requires only signatures by both parties; no witnesses or notary required by statute. Notarization is strongly recommended for enforceability. We HIGHLY recommend having the prenup reviewed and signed with an attorney. Each party keeps a signed original, and so should each party's attorney.
Wyoming Prenuptial Agreement: Frequently Asked Questions (2026)
1. Are prenups enforceable in Wyoming?
Yes. Wyoming courts have recognized prenups (called "antenuptial agreements") as valid and enforceable since Laird v. Laird, 597 P.2d 463 (Wyo. 1979), and the rule has been reaffirmed every time it has been challenged — most recently in Morrison v. Hinson-Morrison, 555 P.3d 944 (Wyo. 2024). Wyoming construes prenups under ordinary contract rules and trial courts must enforce them or articulate a "cogent rationale" on the record for refusing (Lund v. Lund, 1993).
2. Does Wyoming follow the Uniform Premarital Agreement Act (UPAA)?
No. Per the Uniform Law Commission, Wyoming is one of 22 states that have not adopted the UPAA (1983) or the UPMAA (2012). Some online prenup-form sites cite a fabricated "Wyo. Stat. § 20-3-101 to -111" — that statute does not exist. Wyoming Title 20 has no chapter governing premarital agreements; the only on-point statute is the Statute of Frauds, Wyo. Stat. § 1-23-105(a)(iii), which requires the agreement to be in writing.
3. How much does a prenup cost in Wyoming?
A traditional attorney-drafted prenup in Wyoming runs $5,000–$20,000+ for the couple combined (each party retains separate counsel). Online services like HelloPrenup or PerfectPrenup cost a few hundred dollars per couple, with optional attorney review at $500–$1,500 per party. Complex agreements involving ranch land, mineral rights, or business valuations can exceed $15,000.
4. Do I need a lawyer for a prenup in Wyoming?
No. Seherr-Thoss v. Seherr-Thoss, 141 P.3d 705 (Wyo. 2006), expressly held that independent counsel is not required for enforceability. However, separate attorneys for each party dramatically strengthen the agreement against a voluntariness challenge — the most common attack vector — and are strongly recommended.
5. Can a prenup waive alimony in Wyoming?
Yes. Seherr-Thoss (2006) enforced a complete spousal-support waiver. Wyoming has not adopted a public-assistance floor, durational ceiling, or hardship carve-out by statute or case law. Waivers should still be drafted carefully: avoid clauses that would leave a spouse destitute after a long marriage, since general contract unconscionability doctrine still applies.
6. When should I sign a prenup in Wyoming?
There is no statutory minimum waiting period in Wyoming. Best practice: sign 60+ days before the wedding to defeat duress claims, with both parties given 1–2 weeks to review the final draft. Sign before the ceremony — Combs v. Sherry-Combs (1993) invalidated a document signed about a month after the wedding as a postnup that lacked separate consideration.
7. Does a Wyoming prenup need to be notarized?
No, but notarization is universal practice. Wyoming statute requires only that the agreement be in writing and signed by both parties (Wyo. Stat. § 1-23-105(a)(iii)). Witnesses are not required by Wyoming law. Notarization is strongly recommended because it forecloses signature-authenticity challenges.
8. What can a Wyoming prenup cover?
Separate property classification, division of marital assets, debt allocation, alimony amount or waiver, treatment of inheritance and gifts, business interests, mineral rights and royalties, ranch and grazing land, life insurance, estate provisions, and choice of law. Prenups cannot dictate child custody or child support — courts decide those at divorce based on the child's best interests, regardless of what the parents agreed (Combs, 1993).
9. How do I challenge or invalidate a Wyoming prenup?
The challenger bears the burden of proving either (1) involuntary execution by fraud, duress, or denial of opportunity to read, or (2) unconscionability under general contract doctrine. Failure to read the agreement is not a defense for a competent adult (Laird, 1979). Successful challenges in Wyoming have turned on procedural defects — e.g., due process violations (Bradley I, 2005) or a postnup amendment that failed the chosen state's execution formalities (Bradley II, 2007).
10. Can a Wyoming prenup be modified after marriage?
Yes, but with care. A post-marital amendment is a postnuptial agreement and requires separate consideration beyond the marriage itself (Combs, 1993). The amendment must satisfy the same formalities as the original — and if the prenup contains a non-Wyoming choice-of-law clause, the amendment must satisfy that state's formalities too (Bradley II, 2007, invalidating a Wyoming amendment for failing Minnesota's two-witness/notary rule).
11. What happens to property in a Wyoming divorce without a prenup?
Wyoming is an all-property equitable distribution state under Wyo. Stat. § 20-2-114. Courts can divide any property owned by either spouse — including assets acquired before marriage and inherited property — based on what is "just and equitable." A judge in Cheyenne, Casper, or Laramie has broad discretion absent a prenup. A valid prenup overrides this default framework.
12. Will a prenup signed in another state be enforced in Wyoming?
Generally yes, if it was valid where signed and does not violate Wyoming public policy. Most prenups include a choice-of-law clause designating the governing state; Wyoming courts enforce those clauses, including for amendments (Bradley II, 2007). If you are moving to Wyoming, have your existing prenup reviewed by Wyoming counsel — particularly to confirm child-related clauses are severable and that any spousal-support waiver translates cleanly.