Hawaii Knife Laws (2026): Switchblade and Butterfly Rules

Hawaii's core knife statutes are narrower than they first appear. Each of the state's three deadly-weapon provisions, covering a dirk or dagger, a switchblade, and a butterfly knife, bans carrying the item concealed, not owning or carrying it openly, and each carries the same built-in defense for a person lawfully in their own home.

Jurisdiction scope: This page covers Hawaii state law only, principally Haw. Rev. Stat. §§ 134-51, 134-52, 134-53, 134-12.5, and 302A-1134.6. It does not cover Hawaii's separate assault or robbery statutes, which apply to a knife used as a weapon regardless of how it was carried.

Can you own a knife in Hawaii?

Ordinary knife ownership is not restricted by these statutes; each of Hawaii's three deadly-weapon provisions is written as a carrying offense, not a possession ban. Haw. Rev. Stat. § 134-51(a) provides:

Any person, not authorized by law, who knowingly carries 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 shall be guilty of a misdemeanor; provided that this subsection shall not apply to a billy.

Subsection (e) then expressly excludes a switchblade knife and a butterfly knife from this general section, sending both to their own dedicated statutes instead. A "billy," defined in subsection (f) to include a cudgel, truncheon, police baton, collapsible baton, billy club, or nightstick, is excluded from the concealed-carry misdemeanor but is separately reached by subsection (b)'s during-a-crime felony. Subsection (g) provides a defense to the concealed-carry misdemeanor if the person was lawfully present in their own home at the time. On conviction, subsection (d) requires the weapon to be summarily destroyed by the chief of police or sheriff, and a separate statute, Haw. Rev. Stat. § 134-12.5, independently forfeits any firearm, ammunition, deadly or dangerous weapon, or switchblade knife possessed or used in violation of chapter 134 or the Hawaii Penal Code to the State for destruction or transfer to a police department.

The statute's catch-all, "other deadly or dangerous weapon," is not read broadly. In State v. Rackle, 55 Haw. 531, 523 P.2d 299 (1974), the Hawaii Supreme Court held that the phrase reaches only instruments closely associated with criminal activity whose sole design and purpose is to inflict bodily injury or death upon another human being; an object designed for a lawful purpose does not become a "deadly or dangerous weapon" merely because it could be misused. In State v. Giltner, 56 Haw. 374, 537 P.2d 14 (1975), the court built on Rackle to hold that the instrument proscribed is one designed primarily as a weapon, or one that has been diverted from its normal use and prepared and modified for combat purposes, and on that basis held that a diver's knife recovered from the defendant's person was neither a "dagger" nor a "deadly or dangerous weapon" under the statute. An ordinary pocketknife, utility knife, or work knife, carried for its ordinary purpose, is unlikely to be swept into the catch-all on this reasoning, though the outcome still turns on the specific facts.

Open carry

Hawaii's weapons chapter contains no open-carry-specific ban for a dirk, dagger, switchblade, or butterfly knife. Each of the three core statutes discussed on this page is written as a concealed-carry offense specifically; none bans open carry of these items outright. The practical exposure for most readers is not open-carry at all, but whether an ordinary knife counts as an "other deadly or dangerous weapon" under the general concealed-carry statute, § 134-51(a); Hawaii case law narrows that catch-all significantly, discussed below.

Concealed carry: three separate statutes, same structure

Hawaii regulates concealed carry of these knife types through three parallel statutes rather than one general rule.

A switchblade knife is covered by Haw. Rev. Stat. § 134-52:

(a) Whoever knowingly carries concealed on the person, or in a bag or other container carried by the person, any switchblade knife shall be guilty of a misdemeanor. (b) Whoever knowingly possesses or intentionally uses or threatens to use a switchblade knife while engaged in the commission of a separate felony or misdemeanor shall be guilty of a class C felony; provided that a person shall not be prosecuted under this subsection when the separate felony or misdemeanor is an offense otherwise defined by this chapter. ... (d) It shall be a defense to a prosecution under subsection (a) that the person was lawfully present in the person's own home at the time of the offense.

Subsection (e) defines "switchblade knife" as "any knife having a blade that opens automatically by: (1) Hand pressure applied to a button or other device in the handle of the knife; or (2) Operation of inertia, gravity, or both."

A butterfly knife is covered by an identically structured statute, Haw. Rev. Stat. § 134-53, with the same misdemeanor for concealed carry, the same class C felony escalation during a separate crime (including the same same-chapter proviso against double prosecution), and the same home-possession defense at subsection (d). Subsection (e) defines "butterfly knife" as "any knife having a blade encased in a split handle that manually unfolds with hand or wrist action with the assistance of inertia, gravity, or both."

A dirk, dagger, blackjack, or metal knuckles falls under the general provision, § 134-51, described above, which carries the same misdemeanor-for-concealed-carry and class-C-felony-during-a-crime structure, with the home-possession defense at subsection (g) rather than (d). One difference: § 134-51(b)'s felony escalation does not carry the same-chapter proviso that § 134-52(b) and § 134-53(b) do, so all three statutes are not quite identical.

Sections 134-51, 134-52, and 134-53 were each last amended by 2024 Act 21 (sections 4, 5, and 6 respectively). The rule described on this page reflects the statutes as they currently read.

Where you can't carry at all: schools

Haw. Rev. Stat. § 302A-1134.6, the Department of Education's zero tolerance policy, provides that "a child who possesses, sells, or uses a dangerous weapon or switchblade knife, while attending school or while attending department-supervised activities held on or off school property, may be excluded from attending school for up to ninety-two school days." This is a school-discipline provision, separate from the criminal offenses above, and applies specifically to a "dangerous weapon" or a switchblade knife by name.

Does Hawaii preempt local knife ordinances?

Hawaii has no statewide knife preemption statute. The code also sets no minimum age for purchasing or possessing a knife.

Federal law: what it does and does not reach

Federal law does not ban an individual from owning or carrying a switchblade nationwide. The Federal Switchblade Act, 15 U.S.C. §§ 1241 to 1245, instead regulates interstate commerce in switchblade knives, barring their manufacture, sale, transport, or introduction into interstate commerce, and, in 15 U.S.C. § 1245 makes it a federal offense to knowingly possess, manufacture, sell, or import a ballistic knife in or affecting interstate commerce or within federal territorial jurisdiction. 15 U.S.C. § 1244, captioned "Exceptions," provides that §§ 1242 and 1243 "shall not apply to" a list of specific knives; it is an exemption from those two interstate-commerce and importation offenses, not a change to the switchblade definition itself, which sits in § 1241(b) and was not amended. A 2009 addition, § 1244(5), exempts from §§ 1242 and 1243 any knife with a spring, detent, or other closure-bias mechanism that requires hand, wrist, or arm exertion to overcome the bias and assist opening, the exception that keeps modern assisted-opening folding knives legal in interstate commerce. A separate exception, § 1244(4), exempts a person with only one arm from those same two offenses when possessing or carrying a switchblade with a blade three inches or less. Hawaii's own switchblade definition, keyed to how the blade opens rather than its length, operates independently of this federal exception.

Disclaimer: This article provides general legal information about Hawaii's knife laws as of September 2026. It is not legal advice. Consult a lawyer licensed in Hawaii for advice about a specific situation. Because each of these statutes turns on whether the item was "concealed," how a particular knife is carried in practice can affect whether it falls within the offense.

For a state-by-state comparison, see knife laws by state. Hawaii's self-defense statutes are covered separately on the Hawaii self-defense laws page.

Statutes cited reflect their in-force version as of 2026-09-18. Last updated: 2026-09-18.

Frequently Asked Questions

Are switchblades illegal in Hawaii?

Carrying a switchblade knife concealed on the person or in a bag or container is a misdemeanor under Haw. Rev. Stat. 134-52(a). There is a defense if the person was lawfully present in their own home. The statute does not ban open carry.

Are butterfly knives illegal in Hawaii?

Carrying a butterfly knife concealed is a misdemeanor under Haw. Rev. Stat. 134-53(a), with the same structure and home-possession defense as Hawaii's switchblade statute.

Can I carry a dirk or dagger in Hawaii?

Concealed carry of a dirk or dagger is a misdemeanor under Haw. Rev. Stat. 134-51(a), with a defense for lawful presence in one's own home. Switchblade and butterfly knives are expressly excluded from this general section and governed by their own separate statutes.

Can I carry a knife at school in Hawaii?

A student who possesses, sells, or uses a dangerous weapon or a switchblade knife at school or a school-supervised activity may be excluded from school for up to 92 school days under the Department of Education's zero tolerance policy, Haw. Rev. Stat. 302A-1134.6.

Can I carry an ordinary pocketknife or work knife in Hawaii?

Likely yes, based on how Hawaii courts have read the 'other deadly or dangerous weapon' catch-all in section 134-51. In State v. Rackle, the Hawaii Supreme Court limited that catch-all to instruments whose sole design is to inflict death or bodily injury, and in State v. Giltner, applying that test, the court held that a diver's knife was neither a dagger nor a deadly or dangerous weapon under the statute. An ordinary pocketknife or work knife carried for its ordinary purpose is unlikely to fall within the catch-all, though the specific facts still matter.