California Knife Laws 2026 — What's Legal and What's Not

Overview: How California Regulates Knives

California knife law is spread across dozens of Penal Code sections — there is no single "knife statute." The law regulates knives primarily in four ways:

1. Type restrictions: Certain knife types are banned entirely or restricted in how they may be carried (e.g., switchblades, ballistic knives)
2. Concealed carry restrictions: The concealment of "dirks and daggers" is prohibited under Cal. Penal Code § 21310
3. Location restrictions: Knives are prohibited in specific places (schools, government buildings, etc.)
4. Local ordinances: Cities and counties may impose additional restrictions beyond state law

Unlike firearms, California does not have a statewide preemption law for knives. This means that a knife that is legal under state law may be illegal under a city or county ordinance. Always check local laws.

Quick Reference: Knife Legality by Type

* A locking folding knife carried in the open position (locked open, visible in a belt sheath) is treated as a dirk/dagger if concealed. When folded and closed, it is generally treated as a folding knife for concealed carry purposes.

** Possession is prohibited except at home in some interpretations; sale, carry, and transfer are clearly banned.

*** Legal under state law but likely to draw law enforcement attention and may violate local ordinances.

Type-by-Type Breakdown

Folding Knives (Non-Locking)

A standard folding knife without a locking mechanism — such as a traditional slipjoint pocketknife or Swiss Army knife — is the least regulated knife type in California. These knives may be owned, openly carried, and concealed-carried without restriction under state law.

Why? Because under Cal. Penal Code § 17235, a "dirk or dagger" is defined as a knife "that can be readily used as a stabbing weapon that may inflict great bodily injury or death." Non-locking folding knives, when in the closed position, cannot readily be used as stabbing weapons — the blade can fold on the user's hand. Therefore, they are not classified as dirks or daggers and are exempt from the concealed carry prohibition.

Folding Knives (Locking) — Liner Lock, Frame Lock, Axis Lock, etc.

Modern folding knives with locking mechanisms occupy a legal gray area. When the blade is locked open, the knife functions identically to a fixed blade — it can be used as a stabbing weapon. Under PC § 17235, a locking folding knife with the blade in the open and locked position qualifies as a dirk or dagger.

The key question is: does carrying a locking folder in the closed position count as concealing a dirk or dagger?

California courts have generally held that a folding knife carried in the closed and folded position is not a dirk or dagger, because it cannot "readily" be used as a stabbing weapon — the user must first open the blade and engage the lock. However, if the knife is carried open and locked in a concealed manner (e.g., in a pocket with the blade open), it is absolutely a concealed dirk or dagger.

Best practice: Carry locking folders in the closed position. If you carry one open in a sheath, carry it visibly on your belt (open carry).

Fixed Blade Knives / Hunting Knives

Fixed blade knives of any length are legal to own and openly carry in California. There is no statewide blade length limit for fixed blade knives. You can legally walk down the street with a 12-inch Bowie knife on your belt in a visible sheath.

However, fixed blade knives are always classified as dirks or daggers under PC § 17235 and may never be concealed on your person under PC § 21310. Concealing a fixed blade knife — even a small 3-inch blade — is a wobbler offense (can be charged as misdemeanor or felony).

Switchblades (Automatic Knives)

California's switchblade law is found at Cal. Penal Code § 21510. A switchblade is defined as a knife with a blade that "is released automatically by a spring mechanism or other mechanical device" or "that opens, or is ejected open, by the force of gravity or by an outward, downward, or centrifugal thrust or movement."

The law draws a clear line at 2 inches:

Butterfly Knives (Balisongs)

Butterfly knives — also called balisongs — are classified as switchblades under California law. In People v. Quattrone (1989), the California Court of Appeal held that a butterfly knife falls within the definition of a switchblade because its blade is "released" by centrifugal force. As a result, butterfly knives with blades over 2 inches are subject to the same prohibition as switchblades under PC § 21510.

Can you own a butterfly knife? The law prohibits possession "on the person" and "in any vehicle," as well as sale and transfer. Possession at home is not explicitly addressed in the statute, creating some legal ambiguity. However, purchasing one requires a sale or transfer, which is prohibited. In practice, butterfly knives with blades over 2 inches should be avoided entirely.

Karambits

A karambit is a curved, claw-shaped knife originating from Southeast Asia. California does not specifically regulate karambits by name. Instead, their legality depends on their design:

• Fixed-blade karambit: Legal to own and open carry. Concealed carry is prohibited (dirk/dagger under PC § 21310).
• Folding karambit (non-locking): Legal to own, open carry, and conceal carry.
• Folding karambit (locking): Legal to own and open carry. Concealed carry is a gray area — safest to carry in the closed/folded position.

Daggers and Stilettos

Daggers (double-edged blades designed for thrusting) and stilettos are legal to own and openly carry in California. They cannot be concealed under any circumstances — they are the textbook definition of a "dirk or dagger" under PC § 17235.

Machetes

Machetes are legal to own and openly carry under California state law. There is no blade length restriction. They are classified as dirks or daggers when capable of inflicting great bodily injury, so concealed carry is prohibited. In practice, it is difficult to conceal a machete, but carrying one under a coat or in a bag would violate PC § 21310.

Swords

Swords are legal to own and technically legal to open carry under state law — California does not have a specific statute banning swords. However:

• Concealed carry is prohibited (dirk/dagger)
• Local ordinances may prohibit open carry of swords
• You may be stopped and questioned by law enforcement under PC § 417 (brandishing) if the manner of carry creates alarm
• Carrying a sword in a public place is likely to result in a police encounter regardless of technical legality

Ballistic Knives

A ballistic knife — a knife with a blade that can be expelled from the handle as a projectile — is completely banned in California. Under Cal. Penal Code § 21110, it is illegal to possess, sell, offer for sale, or loan a ballistic knife. Violation is a wobbler offense (misdemeanor or felony).

The Blade Length Myth

One of the most persistent myths about California knife law is that there is a maximum legal blade length — commonly cited as 3 inches, 4 inches, or 6 inches. This is false under state law.

California state law does not impose a general blade length restriction. You can legally carry a knife with a 12-inch blade, provided it is carried openly and is not a prohibited type (switchblade over 2 inches, ballistic knife, etc.).

However, some local ordinances do impose blade length limits. For example, the City of Los Angeles Municipal Code § 55.10 prohibits concealed carry of knives with blades over 3 inches. Always check your local city and county ordinances.

Concealed Carry of Dirks and Daggers: PC 21310

Cal. Penal Code § 21310 is the central concealed carry statute for knives. It states:

"Except as provided in Section 21390, any person in this state who carries concealed upon the person any dirk or dagger is punishable by imprisonment in a county jail not exceeding one year or imprisonment pursuant to subdivision (h) of Section 1170."

This is a wobbler offense — it can be charged as either a misdemeanor (up to 1 year county jail) or a felony (16 months, 2, or 3 years state prison) depending on the circumstances and the defendant's criminal history.

A "dirk or dagger" is defined in PC § 17235 as "a knife or other instrument with or without a handguard that is capable of ready use as a stabbing weapon that may inflict great bodily injury or death." The definition includes:

• All fixed blade knives (regardless of size)
• Locking folding knives when in the open and locked position
• Any knife worn in a sheath and carried concealed on the person

"Concealed" means hidden from ordinary observation. If you can see the knife (e.g., a belt sheath visible outside your clothing), it is open carry and legal. If the knife is under your clothing, in your pocket (blade open), or otherwise hidden from view, it is concealed.

Restricted Locations

Certain locations prohibit knives regardless of type or carry method:

Schools (K-12)

Under Cal. Penal Code § 626.10, it is illegal to bring any knife with a blade longer than 2.5 inches, any folding knife with a locking blade, any ice pick or similar sharp tool, any razor, or any dirk or dagger onto K-12 school grounds. Exceptions exist for authorized use in food preparation, instruction, or maintenance.

Government Buildings

Under Cal. Penal Code § 171b, it is illegal to bring any knife with a blade over 4 inches, any switchblade, or any "deadly weapon" into any state or local government building. Courthouses have even stricter restrictions.

Airports and Federal Buildings

Federal law and TSA regulations prohibit knives in airport secure areas and on aircraft. You may not bring any knife through a TSA checkpoint. Knives may be packed in checked luggage only.

National Parks and Federal Land

Under 36 C.F.R. § 2.4, possessing a weapon in a national park is generally governed by the law of the state where the park is located. However, weapons are prohibited inside federal buildings within parks (visitor centers, ranger stations).

Teter v. Lopez and Second Amendment Knife Rights

In Teter v. Lopez (2024), the U.S. Court of Appeals for the Ninth Circuit considered whether Hawaii's ban on butterfly knives violated the Second Amendment under the Bruen framework. The Ninth Circuit held that butterfly knives qualify as "arms" protected by the Second Amendment's plain text, and remanded the case for further proceedings on whether Hawaii could justify its ban under the historical tradition test.

This decision is significant for California because:

• It establishes that knives are "arms" under the Second Amendment in the Ninth Circuit (which includes California)
• It suggests that California's treatment of butterfly knives as switchblades may be subject to constitutional challenge
• It opens the door to Second Amendment challenges to other knife restrictions

The full impact of Teter on California knife law is still developing. Track this case on our Law Tracker.

Penalties for Knife Law Violations

Federal Knife Laws

Federal law generally does not regulate knife ownership or carry, with a few exceptions:

• Switchblade Act (15 U.S.C. § 1241–1245): Prohibits the interstate transport of switchblades for commercial purposes. This does not prohibit individual possession or carry — it restricts commercial interstate shipment. Personal carry is governed by state law.
• Federal buildings: Under 18 U.S.C. § 930, it is illegal to bring a "dangerous weapon" (including knives) into a federal building. Penalties include up to 1 year imprisonment.
• TSA regulations: Knives of any type are prohibited in carry-on luggage on commercial flights. They may be packed in checked luggage.
• National parks: State law applies; federal building restrictions apply within park facilities.

TSA Rules for Knives

If you are flying out of or through California:

• Carry-on: NO knives of any kind are permitted through TSA checkpoints, with the exception of plastic or round-bladed butter knives.
• Checked luggage: Knives are permitted in checked luggage. They should be securely wrapped or sheathed to prevent injury to baggage handlers.
• Multi-tools: Multi-tools with blades (Leatherman, Gerber, etc.) are prohibited in carry-on but permitted in checked luggage.

Practical Advice: Choosing a Legal Everyday Carry Knife

If you want to carry a knife daily in California with minimum legal risk, follow these guidelines:

1. Choose a non-locking folding knife if you want to carry concealed. Slipjoint knives from traditional makers (Case, Buck 55, Victorinox) and modern friction folders are the safest choice.
2. If you prefer a locking folder (and most people do for safety reasons), carry it in the closed position and be aware of the legal gray area. Many Californians carry locking folders daily without issue, but understand the risk.
3. If you carry a fixed blade, carry it openly in a belt sheath visible outside your clothing. Never tuck it under your shirt or jacket.
4. Check your local ordinances. If you are in Los Angeles, San Francisco, or other major cities, there may be blade length limits for concealed carry that do not exist under state law.
5. Avoid prohibited types: No switchblades over 2 inches, no butterfly knives, no ballistic knives.

Conclusion

California knife law is more permissive than many people assume — but it contains traps for the unwary. The core rules are: you can openly carry almost any legal knife; you cannot conceal a dirk or dagger (fixed blades and locked-open folders); switchblades over 2 inches and butterfly knives are banned; and local ordinances may add additional restrictions.

The legal landscape is also evolving. The Ninth Circuit's decision in Teter v. Lopez recognizing knives as Second Amendment "arms" may lead to challenges against some of California's knife restrictions. Stay informed through our 2A Legal tools and blog.

When in doubt, carry a non-locking folding knife in your pocket. It is legal everywhere in California under state law, and it is the one knife type that creates zero legal ambiguity.