Wisconsin: C+
Statutes
Wisconsin Statute § 766.58
Separate Property
All assets can remain separate property, avoiding costly divorce settlements. Joint assets and debts titled in both names are split 50/50 as marital property.
Unconscionability at Execution AND Enforcement
Wisconsin applies a "two looks" standard—courts review unconscionability both at execution AND at enforcement. A prenup may be invalidated if it was unfair when signed OR if unforeseeable changed circumstances make it unfair at divorce.
Unconscionability Standard
A prenup is unenforceable if the challenging spouse proves ANY of: (1) unconscionable when made, OR (2) involuntary execution, OR (3) lack of fair financial disclosure without actual notice of the other's finances.
Public Assistance Spousal Support Floor
Spousal support can be waived entirely, but courts may override waivers if enforcement would make one spouse eligible for public assistance. Courts can require only enough support to avoid public assistance eligibility, notwithstanding the prenup.
Timing
No minimum specified, but we recommend signing the prenup at least 30-60 days before the wedding, with both parties having 2-3 weeks to review the final version to minimize challenge risk.
Independent Counsel
Not required, but separate counsel dramatically strengthens enforceability if the agreement is later challenged.
Financial Disclosure
"Fair and reasonable disclosure" of property and financial obligations required, statute does not address if written waiver is acceptable (PerfectPrenup includes both out of precaution).
Medium Burden to Challenge
Challenging party must prove the prenup is invalid by preponderance of evidence (standard civil burden, not clear and convincing).
Child Support and Custody
Child support and custody clauses are unenforceable and could undermine the entire agreement. Do not include.
Case Law
Wisconsin's biggest weakness is where married couples operate a business together. To avoid equal division when one party provides minimal contributions, a contract should be drawn outlining responsibilities and ownership percentage.
Brandt v. Brandt, 145 Wis. 2d 394, 427 N.W.2d 126 (Ct. App. 1988)
The court declined to enforce a postnuptial agreement where the parties completely ignored it throughout the marriage and commingled their assets so thoroughly that meaningful enforcement was impossible.
Krejci v. Krejci, 2003 WI App 160, 266 Wis. 2d 284, 640 N.W.2d 207 (2003)
The court refused to enforce a prenuptial agreement excluding an inherited resort from the marital estate because the parties operated it as a partnership for 18 years, never discussed the agreement during the marriage, commingled their finances, and both spouses' efforts contributed to the resort's appreciation in value.
Steinmann v. Steinmann, 309 Wis. 2d 29, 749 N.W.2d 145, 2008 WI 43 (2008)
The court held that when separate property is used to purchase property that is then titled jointly, this demonstrates donative intent and transmutes the property from individual to marital property, resulting in Rose being ordered to pay Tony $764,000 for his share of their $2.2 million Lake Geneva home despite it being purchased partially with her individual settlement funds.
Button v. Button, 131 Wis. 2d 84, 388 N.W.2d 546 (1986)
The Wisconsin Supreme Court reversed the circuit court's enforcement of a 1974 postnuptial agreement and established the foundational "Button test" requiring prenuptial agreements to satisfy three requirements: fair and reasonable financial disclosure, voluntary and free entry, and substantive fairness both at execution and at enforcement.
Gardner v. Gardner, 190 Wis. 2d 216, 527 N.W.2d 701 (Ct. App. 1994)
The court upheld a prenuptial agreement giving the husband (who had over $3 million in assets) substantially all marital property, finding that five days' notice before the wedding was adequate when the wife had independent counsel, and that disparity in property division alone does not make an agreement unfair.
Greenwald v. Greenwald, 154 Wis. 2d 767, 454 N.W.2d 34 (Ct. App. 1990)
The court enforced a premarital agreement between a retired 70-year-old widower and his former housekeeper, holding that if a party's conduct demonstrates that specific knowledge of the other party's property and finances is not important to them, the agreement may not be defective even without formal financial disclosure.