Wisconsin generally allows lawful adults to own and carry common knives, including automatic knives, without a statewide blade-length limit. A major 2016 change removed knives from the ordinary concealed-weapon offense and repealed the former switchblade prohibition. [1] [2]
The pre-2016 three-inch concealed-carry exception is not current Wisconsin law. For most people, concealment and blade length alone do not make an ordinary knife illegal.
Which knives can adults own?
2015 Wisconsin Act 149 repealed the state switchblade ban. Manual folders, fixed blades, automatic knives, OTF knives, and balisongs are not generally prohibited by a current statewide ownership rule based only on design or opening method. [1]
Wisconsin’s general definition of “dangerous weapon” is context based. It includes a device designed as a weapon and capable of producing death or great bodily harm, and an instrument that, in the manner used or intended to be used, is calculated or likely to produce that harm. An ordinary knife can therefore become a dangerous weapon depending on design, use, or intended use. [3]
What are the open- and concealed-carry rules?
Section 941.23 expressly states that “dangerous weapon” does not include a knife for the ordinary concealed-weapon offense. Wisconsin DOJ guidance explains that a concealed-carry license is not required merely to carry a concealed knife. [1] [2]
A separate rule, § 941.231, applies to a person prohibited from possessing a firearm under § 941.29 who goes armed with a concealed knife that is a dangerous weapon. Threats, disorderly conduct supported by criminal or malicious intent, assault, or use during another crime can also create liability. [4]
How do vehicle carry and transport work?
The former “three-inch limit” should not be applied to a knife in a vehicle. The current ordinary concealed-weapon statute excludes knives. A prohibited person covered by § 941.231 remains subject to that separate concealed-knife rule. Property rules and restricted-location statutes may also apply.
What age and school rules matter?
Wisconsin does not impose a blanket three-inch purchase or possession rule on minors in the cited current statutes. Section 948.60 has its own enumerated definition of dangerous weapon that does not list knives. A knife can still be regulated under other laws or policies depending on its use, intended use, location, or the conduct involved. [5]
Section 948.61 prohibits knowingly possessing or going armed with a dangerous weapon on school premises. Wisconsin DOJ guidance confirms that Act 149 did not remove this school restriction. Not every ordinary pocketknife is automatically a dangerous weapon in every context, but a knife designed, used, or intended as a weapon may qualify. Schools may also enforce broader student and visitor policies. [1] [6]
Does Wisconsin preempt local knife ordinances?
Section 66.0409 generally prevents a political subdivision from regulating the sale, purchase, ownership, use, possession, bearing, or transportation of a knife more stringently than state law. It does allow a political subdivision to prohibit knives in a building or part of a building that it owns, occupies, or controls. [7]
The Wisconsin Supreme Court has held that the statute prevents Madison from enforcing a more restrictive knife rule on city buses when the carry otherwise complies with state law. [8]
Practical takeaway
Wisconsin has no current general three-inch concealed-carry limit and no statewide switchblade ban. Carry for lawful purposes, respect school and government-building rules, and remember that a prohibited person faces a separate concealed-knife restriction.
Last reviewed: August 24, 2026.
This article provides general information, not legal advice. Wisconsin knife law can depend on the carrier’s legal status, the knife’s design, intended use, conduct, school or property rules, local-building restrictions, federal law, and court interpretation. Verify current official sources or consult a qualified Wisconsin attorney about a specific situation.
Sources & References
- [1] Wisconsin DOJ Concealed Carry Curriculum, Appendix F—Knives. Official explanation of 2015 Act 149, concealed carry, school rules, and local regulation.
- [2] Wis. Stat. § 941.23. Ordinary concealed-weapon offense; knives excluded from its dangerous-weapon definition.
- [3] Wis. Stat. § 939.22(10). General dangerous-weapon definition.
- [4] Wis. Stat. § 941.231. Concealed dangerous knife carried by a person prohibited from firearm possession.
- [5] Wis. Stat. § 948.60. Current minor-possession rule and its specific dangerous-weapon definition.
- [6] Wisconsin State Law Library: § 948.61 elements. Dangerous weapons other than firearms on school premises.
- [7] Wis. Stat. § 66.0409. Local knife preemption and government-building exception.
- [8] Wisconsin Carry, Inc. v. City of Madison, 2017 WI 19. Wisconsin Supreme Court decision applying § 66.0409 to knife restrictions.
