Hawaii’s knife law changed materially in 2024. Older summaries often say that switchblades and butterfly knives are completely prohibited, but that is no longer accurate. Act 21 removed the former statewide bans on manufacturing, selling, transferring, possessing, and transporting those knives. The current statutes instead focus on concealed carry and on possession or use during a separate crime.[1]
This distinction is important for residents, visitors, retailers, and collectors: lawful ownership is not the same as lawful carry.
Can you own switchblades and butterfly knives in Hawaii?
Yes. Under the law in effect after Act 21 of 2024, Hawaii no longer imposes a blanket statewide prohibition on the manufacture, sale, transfer, possession, or transport of switchblade and butterfly knives.[1]
Hawaii still defines the two categories separately:
- Switchblade knife: a knife with a blade that opens automatically by pressure on a button or other device in the handle, or by inertia, gravity, or both.[2]
- Butterfly knife: a knife with a blade encased in a split handle that manually unfolds with hand or wrist action assisted by inertia, gravity, or both.[3]
Automatic, OTF, and balisong owners should nevertheless follow the carry restrictions below. A knife may be lawful to own at home but unlawful to carry concealed in public.
What is the concealed-carry rule?
HRS §134-52 makes it a misdemeanor to knowingly carry a switchblade knife concealed on the person, or in a bag or other container carried by the person.[2] HRS §134-53 applies the same concealed-carry rule to butterfly knives.[3]
Both sections provide a defense when the person was lawfully present in the person’s own home. They also create a class C felony for knowingly possessing, intentionally using, or threatening to use the covered knife while engaged in a separate felony or misdemeanor, subject to the wording and exceptions in the statutes.
What about ordinary pocket knives and fixed blades?
HRS §134-51 prohibits knowingly carrying concealed on the person—or in a bag or other container carried by the person—a dirk, dagger, blackjack, metal knuckles, or another “deadly or dangerous weapon.”[4]
Hawaii case notes distinguish ordinary tools from weapons designed primarily to injure. They state, for example, that a diver’s knife was not a “dangerous weapon” or dagger, and that kitchen knives were not automatically deadly or dangerous weapons. Classification can still change when an object is altered, prepared, carried, or used as a weapon.[4]
Because “ordinary pocket knife” is not a universal statutory safe-harbor label, consider the knife’s design, condition, manner of carry, location, and purpose. Avoid treating an exposed pocket clip as guaranteed proof of lawful open carry.
Does Hawaii have a general blade-length limit?
Chapter 134 does not create one general statewide blade-length limit that makes every knife above or below a certain measurement lawful or unlawful. Knife type and manner of carry matter more under §§134-51 through 134-53.
Specific properties and institutions may adopt their own limits. For example, University of Hawaii management-area rules prohibit knives with blades longer than three inches, along with other weapons, subject to stated exceptions.[5]
Can you transport a knife in a vehicle?
Act 21 removed the former “within any vehicle used or occupied by the person” language from HRS §134-51. The current text focuses on concealed carry on the person or in a bag or container carried by the person.[1]
That change should not be read as permission to carry any knife in any vehicle or location. A knife used in a crime, carried into a prohibited facility, or handled contrary to property or carrier rules can still create legal problems. For safer transport, keep the knife closed or sheathed, secured against accidental access, and separated from immediate use.
What locations require extra caution?
- Schools and campuses: student-discipline rules and institutional weapons policies can be broader than the general state carry statutes.
- Courthouses and government facilities: security rules may prohibit knives even when the knife is otherwise lawful.
- Airports: passenger-screening rules apply in addition to state law.
- Private property and events: owners, venues, and carriers can impose entry conditions.
- Federal property: federal facility and agency rules may apply.
University and school policies can prohibit even tools that state criminal law does not categorically ban. Check the current policy for the exact campus, workplace, venue, or government facility before arriving with a knife.
Are there special age restrictions?
Hawaii does not provide one simple statewide age rule governing possession of every knife type in every setting. School discipline rules, parental supervision, retailer policies, unlawful-purpose laws, and location rules can all affect minors. Do not rely on the old article’s blanket statement that all independent knife possession is prohibited under age 18.
Can counties add knife restrictions?
Do not assume that a lawful knife under Chapter 134 is automatically permitted by every county, facility, event, or property owner. Hawaii does not present the same broad knife-preemption language found in some other states. Verify the current county code and the rules of the property or venue where you plan to carry.
How should you travel with a knife?
- Confirm the rules at your destination, including inter-island carrier policies.
- Use a sheath, case, or secure compartment that prevents accidental opening.
- Do not carry switchblades or butterfly knives concealed on your person or in a bag you are carrying.
- For air travel, place knives in checked baggage; TSA generally prohibits knives in carry-on bags except for limited plastic or round-bladed butter-knife exceptions.[6]
Practical takeaway
Hawaii no longer bans ownership of switchblade and butterfly knives. The central current rule is that these knives may not be knowingly carried concealed on the person or in a bag or container carried by the person. Ordinary pocket knives and fixed blades require a more fact-specific analysis under the state’s “deadly or dangerous weapon” language, case law, and location policies.
Last reviewed: August 24, 2026
This article provides general educational information and is not legal advice. Laws, regulations, court decisions, and local or property rules can change. Verify the current law through official Hawaii sources or consult a qualified Hawaii attorney before relying on this information.
Sources & References
- [1] Hawaii Session Laws 2024 — Act 21, amendments to HRS §§134-51, 134-52, and 134-53
- [2] Hawaii Revised Statutes §134-52 — Switchblade knives; prohibitions; penalty
- [3] Hawaii Revised Statutes §134-53 — Butterfly knives; prohibitions; penalty
- [4] Hawaii Revised Statutes §134-51 — Deadly or dangerous weapons; prohibitions; penalty, with case notes
- [5] University of Hawaii Administrative Rules, Chapter 20-26 — Management-area weapons restrictions
- [6] Transportation Security Administration — Knives in carry-on and checked baggage
