Hawaii knife law changed in a major way in 2024. As of March 2026, Hawaii no longer broadly bans the ownership, sale, manufacture, or transport of switchblades, butterfly knives, or gravity knives statewide. The main statewide risk now is concealed carry of certain knives, especially dirks, daggers, switchblades, butterfly knives, and other knives treated as deadly or dangerous weapons under Chapter 134. This article provides legal information, not legal advice.
Quick Answer
Hawaii law now focuses more on how a knife is carried than on mere ownership.
That is the practical effect of Act 21. Before May 13, 2024, Hawaii had broad bans on switchblades and butterfly knives. After Act 21, those broad possession and transfer bans were removed, and the statutes were rewritten to target concealed carry and criminal misuse instead. That means the current analysis in Hawaii usually starts with three questions: what kind of knife it is, whether it is concealed, and whether it is being carried or used in connection with another offense.
Most knives are legal to own in Hawaii under the current statewide law.
That includes ordinary folding knives, fixed blades, hunting knives, utility knives, kitchen knives, switchblades, butterfly knives, and gravity knives. Act 21 removed the former statewide bans on manufacturing, selling, transferring, possessing, or transporting switchblades and butterfly knives. Because Hawaii defines a switchblade to include a blade that opens automatically by inertia or gravity, gravity knives fall into the same general state-law category for Chapter 134 analysis.
The statutes reviewed did not identify a general statewide ownership ban on ordinary knives after Act 21. The more important issue is carry method, not ownership alone.
Open carry is generally the lower-risk form of knife carry under current Hawaii law.
The current text of HRS §§ 134-51(a), 134-52(a), and 134-53(a), as amended by Act 21, is aimed at concealed carry on the person or in a bag or other container carried by the person. The prior wording in HRS § 134-51 that reached a person who was “found armed” or carrying within a vehicle was removed in the 2024 rewrite. As a result, Hawaii’s knife statutes no longer read like a broad statewide ban on simply openly carrying a knife in public.
That said, open carry is not risk-free. If a knife is used, possessed, or threatened during the commission of a separate felony or misdemeanor, Hawaii law imposes a class C felony under HRS §§ 134-51(b), 134-52(b), and 134-53(b). Open carry also becomes more legally sensitive when the knife is a combat-style blade or when the facts suggest intimidation, unlawful intent, or entry into a restricted place.
Concealed carry is where Hawaii law remains strict.
HRS § 134-51(a) prohibits knowingly carrying concealed on the person, or in a bag or other container carried by the person, any dirk, dagger, blackjack, metal knuckles, or other deadly or dangerous weapon. HRS § 134-52(a) separately prohibits concealed carry of a switchblade knife. HRS § 134-53(a) separately prohibits concealed carry of a butterfly knife.
This matters because Hawaii no longer treats switchblades and butterfly knives as generally unlawful to own, but it still treats concealed carry of those knives as a misdemeanor. The same practical risk applies to gravity knives because Hawaii’s switchblade definition includes knives that open automatically by inertia, gravity, or both.
For ordinary folding or utility knives, the analysis is narrower. Hawaii case law has long read “other deadly or dangerous weapon” in HRS § 134-51 narrowly, limiting it to instruments whose sole design and purpose is to inflict bodily injury or death, and later cases treated items like a diver’s knife, kitchen knife, or butterfly knife differently depending on design and context. That means not every ordinary pocket knife automatically becomes a prohibited concealed weapon under HRS § 134-51. Still, if a knife is designed primarily as a weapon, concealed carry becomes much riskier.
Hawaii also created home-related defenses in the 2024 amendments. HRS § 134-51(g), HRS § 134-52(d), and HRS § 134-53(d) provide a defense where the person was lawfully present in that person’s own home at the time of the offense.
Yes for ownership, but not always for concealed carry.
Automatic knives and switchblades are legal to own in Hawaii after Act 21, but concealed carry remains prohibited under HRS § 134-52(a). Butterfly knives are also legal to own, sell, and possess statewide after Act 21, but concealed carry remains prohibited under HRS § 134-53(a). Gravity knives are not listed by separate name in the current statute, but Hawaii’s switchblade definition includes knives that open by inertia or gravity, so concealed carry of a gravity knife should be analyzed under HRS § 134-52.
Double-edged knives require more caution. Hawaii statutes do not create a separate statewide ownership ban on “double-edged knives” by that label. But a double-edged blade may often be treated as a dagger or dirk for carry purposes, which makes concealed carry risky under HRS § 134-51(a). Open carry of such a knife is not expressly banned statewide by Chapter 134, but the legal risk rises with weapon-like design, location, and surrounding facts.
No general statewide blade-length limit was identified in Hawaii’s knife statutes reviewed.
That is one of the main corrections needed in the current article. Hawaii’s Chapter 134 knife provisions are not written around a general inch-based statewide limit. Instead, they focus on knife type, concealment, and criminal misuse.
That does not mean blade length never matters. Specific places or rules can use their own length limits. For example, the University of Hawaiʻi rule for certain management areas prohibits knives with a blade length greater than three inches there. But that is a place-specific rule, not a general statewide carry limit.
Hawaii does not appear to use one broad statewide knife-sensitive-places statute, but restricted-place rules still matter.
The current statewide knife statutes reviewed do not create a single, firearm-style list of all forbidden knife locations. Still, several narrower location-based issues remain important:
First, school-related settings are stricter. HRS § 302A-1134.6 creates a zero-tolerance school discipline rule for a child who possesses, sells, or uses a dangerous weapon or switchblade knife while attending school or department-supervised activities. That statute is not a general statewide adult carry statute, so it should not be overstated, but it clearly shows that school environments receive stricter treatment.
Second, some university-controlled areas have their own rules. In the University of Hawaiʻi management areas, Hawaiʻi Administrative Rules § 20-26-27 prohibit knives with a blade length greater than three inches, subject to stated exceptions.
Third, airport screening remains a practical restriction. TSA rules prohibit knives in carry-on baggage, even if Hawaii state law would otherwise permit ownership or ground carry. For air travel, federal screening rules matter separately from Hawaii state law.
No broad statewide age or sale restriction for ordinary knives was identified in the Hawaii statutes reviewed after Act 21.
That is a cautious statement, not a promise that no age-related issue can ever arise. Hawaii school discipline rules can affect minors in school settings, and private retailers may impose their own policies. But the current statewide knife statutes reviewed did not reveal a general Hawaii rule that bans ordinary knife sales or possession merely because a person is under a certain age.
No broad statewide knife-law preemption provision was identified in the Hawaii statutes reviewed.
That means Hawaii does not appear to have a clear statewide rule wiping out every county or property-specific knife restriction. As a practical result, a person cannot rely on Chapter 134 alone when carrying a knife into public facilities, special-use lands, or locally regulated property.
Yes, local and property-specific rules can still matter in Hawaii.
Because no broad statewide knife-law preemption provision was identified, local restrictions cannot be dismissed out of hand. The materials reviewed did not identify a major, current, countywide knife ordinance that changes the basic statewide carry rules in the same way Act 21 did. But the lack of preemption means county, campus, park, facility, and other property-specific rules still deserve a separate check before carry.
The safer legal takeaway is simple: Hawaii’s state statutes are now more permissive on ownership, but they are not the only rules that matter.
Federal law still matters even when Hawaii law is comparatively permissive.
The Federal Switchblade Act, 15 U.S.C. §§ 1241-1245, still regulates switchblades in interstate commerce and in certain federal jurisdictions, with exceptions set out in 15 U.S.C. § 1244. Mailing rules are also separate from Hawaii law. Under 18 U.S.C. § 1716, ballistic knives and certain other knives face federal mailing restrictions. And for travel, TSA rules still prohibit knives in carry-on bags.
So a knife may be lawful to own in Hawaii but still create separate issues when mailed, shipped, brought through airport screening, or carried in a federal setting.
| Issue | Practical takeaway |
|---|---|
| Owning switchblades, butterfly knives, and gravity knives | Generally lawful statewide after Act 21. |
| Open carry of an ordinary knife | Generally lower risk under current Hawaii statutes because the current text focuses on concealed carry, not mere public possession. |
| Concealed carry of switchblades, butterfly knives, and gravity knives | Still prohibited statewide under HRS §§ 134-52 and 134-53, with gravity knives analyzed through the switchblade definition. |
| Concealed carry of daggers or dirks | High risk under HRS § 134-51(a). |
| Concealed carry of an ordinary pocket or utility knife | Usually a better position than carrying a weapon-designed knife, but classification can still turn on design and facts. |
| Statewide blade-length limit | No general statewide limit identified in Chapter 134. |
| Carry in the home | The 2024 amendments added home-based defenses to the main concealed-carry sections. |
| Special places | School, university, airport, and other property-specific rules can impose extra restrictions even where state ownership is lawful. |
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Hawaii’s major recent knife-law change is already in force.
H.B. 2342 became Act 21 on May 13, 2024. That law removed Hawaii’s former broad bans on switchblades and butterfly knives and rewrote the core carry provisions discussed above.
A later proposal, S.B. 433, would have moved the law in the opposite direction by restricting open carry of deadly or dangerous weapons and adding “bladed weapon” language. But as of March 20, 2026, S.B. 433 is not law. The bill was carried over to the 2026 Regular Session and then deferred by committee on February 2, 2026.
Yes. Hawaii now generally allows ownership and possession of switchblades. But concealed carry of a switchblade remains prohibited under HRS § 134-52(a).
Yes. Hawaii now generally allows ownership and possession of butterfly knives. But concealed carry of a butterfly knife remains prohibited under HRS § 134-53(a).
Generally yes for ownership under current Hawaii law. But because Hawaii’s switchblade definition includes knives opening by inertia or gravity, concealed carry should be analyzed under HRS § 134-52.
The 2024 amendments removed the older vehicle wording from HRS § 134-51. The current knife sections focus on concealed carry on the person or in a bag or container carried by the person. That is more favorable than the old text, but the exact facts still matter.
No general statewide blade-length limit was identified in Hawaii’s knife statutes reviewed. Some place-specific rules, however, do use their own limits.
Not necessarily. Hawaii case law has historically treated “other deadly or dangerous weapon” narrowly, and ordinary utility or pocket knives are not automatically placed in the same category as daggers or dirks. Design and context still matter.
Laws can change, local rules may still apply, and restricted places, intent, and case-specific facts can change the legal result.
Hawaii official sources
Federal official sources
Optional secondary sources