Are Automatic Knives Legal in California?

The Short Answer

It's complicated — and California makes it more complicated than it needs to be.

You can own an automatic knife in California. But you cannot carry, possess in a vehicle, or transfer a switchblade with a blade of two inches or longer. An automatic knife with a blade under two inches is legal to carry. That two-inch limit effectively bans most practical automatic knives from carry, since very few production automatics have blades that short.

On top of the switchblade restriction, California has a broad "dirk or dagger" concealed carry prohibition that affects fixed blade knives and locking folders carried concealed. And local cities — especially San Francisco and Los Angeles — layer on additional restrictions.

If you're a knife person moving to or traveling through California, read this carefully.

What California Law Actually Says

The Switchblade Statute (Penal Code § 21510)

The primary statute governing automatic knives is California Penal Code § 21510:

"Every person who does any of the following with a switchblade knife having a blade two or more inches in length is guilty of a misdemeanor:

(a) Possesses the knife in the passenger's or driver's area of any motor vehicle in any public place or place open to the public.

(b) Carries the knife upon the person.

(c) Sells, offers for sale, exposes for sale, loans, transfers, or gives the knife to any other person."

This is the core restriction. A switchblade with a blade two inches or longer cannot be carried on your person, kept in your vehicle in public, or sold/transferred.

The Definition of "Switchblade" (Penal Code § 17235)

California defines "switchblade knife" in § 17235:

"'Switchblade knife' means a knife having the appearance of a pocketknife and includes a spring-blade knife, snap-blade knife, gravity knife, or any other similar type knife, the blade or blades of which are two or more inches in length and which can be released automatically by a flick of a button, pressure on the handle, flip of the wrist or other mechanical device, or is released by the weight of the blade or by any type of mechanism whatsoever."

The definition continues with the critical assisted-opener exception:

"'Switchblade knife' does not include a knife that opens with one hand utilizing thumb pressure applied solely to the blade of the knife or a thumb stud attached to the blade, provided that the knife has a detent or other mechanism that provides resistance that must be overcome in opening the blade, or that biases the blade back toward its closed position."

What That Means in Plain English

California enacted its switchblade restriction in 1957 and has kept it. The two-inch blade length is the bright line. Measure the entire blade — including any unsharpened portion — and if it's two inches or more, the knife cannot be carried, kept in your car, or sold in California if it's an automatic.

Automatics with blades under two inches? Legal to carry. Automatics with blades two inches or longer? Legal to own at home. Cannot be carried in public, kept in a vehicle, or sold.

The assisted-opener exception (the "bias toward closure" language) was added in part through AKTI advocacy. If your knife needs manual thumb pressure to start opening and has a detent or spring biasing it toward the closed position, it's not a switchblade under California law — regardless of blade length.

OTF Knives in California

OTF knives fall squarely under California's switchblade definition. An out-the-front automatic knife with a blade of two inches or more is illegal to carry on your person, possess in a vehicle in public, or sell/transfer in California.

Can you own one at home in California? The statute specifically targets carrying, vehicle possession in public, and sale/transfer. Home possession is not explicitly prohibited by § 21510. But the practical reality is: if you can't carry it, transport it in your car, or buy it in-state, "legal to own at home" is a very narrow permission.

OTF knives with blades under two inches — there are a few micro OTFs on the market — would be legal to carry.

San Francisco note: The city of San Francisco has a local ordinance that prohibits switchblades of any length. The state's two-inch exception doesn't apply within San Francisco city limits.

Switchblades vs. Automatic Knives: What California Considers Them

California uses the term "switchblade knife" and defines it broadly in § 17235. Under California law:

• Switchblade / Automatic knife / OTF: All fall under § 17235 if the blade is two inches or longer and deploys automatically. Subject to the carry, vehicle, and sale restrictions of § 21510.
• Gravity knife: Specifically included in the switchblade definition. Same restrictions apply.
• Assisted opener: Explicitly excluded from the switchblade definition by the bias-toward-closure exception. Legal in California regardless of blade length (though still subject to dirk/dagger rules if carried concealed with blade locked open).

The Dirk and Dagger Problem (Penal Code § 21310 / § 16470)

Beyond the switchblade restriction, California has a separate concealed carry prohibition that affects many knife types.

Penal Code § 21310 makes it unlawful to carry any "dirk or dagger" concealed on your person.

§ 16470 defines "dirk or dagger" 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 statute adds:

"A nonlocking folding knife, a folding knife that is not prohibited by Section 21510, or a pocketknife is capable of ready use as a stabbing weapon that may inflict great bodily injury or death only if the blade of the knife is exposed and locked into position."

This means:

• Any fixed blade knife can be a dirk or dagger and cannot be carried concealed
• Any folding knife with a locking blade (when blade is locked open) can be a dirk or dagger
• Non-locking (slip joint) folding knives are only dirks/daggers if the blade is open and exposed

The People v. Castillolopez (2016) California Supreme Court decision confirmed that a non-locking folding knife (like a Swiss Army knife) is not "locked into position" when open, and therefore is not a dirk or dagger.

However, the State v. Hester (2020) decision upheld a conviction for concealed dirk/dagger possession for two box cutters with one-inch blades — meaning there's no minimum blade length for a dirk/dagger charge.

For fixed blades: Carry openly in a sheath suspended from the waist. Penal Code § 20200 provides:

"A knife carried in a sheath that is worn openly suspended from the waist of the wearer is not concealed."

Carrying an Automatic Knife in California

Open Carry

For automatic knives with blades two inches or longer: no. The § 21510 prohibition covers carrying "upon the person" — it doesn't distinguish between open and concealed carry. An automatic knife with a two-inch-plus blade cannot be carried at all in California, openly or concealed.

For automatic knives with blades under two inches: legal to carry openly.

For non-automatic knives: open carry is legal, and it's the required method for fixed blades (carried in a belt sheath) to avoid the dirk/dagger concealed carry prohibition.

Concealed Carry

Concealed carry of any automatic knife with a blade two inches or longer is prohibited. Concealed carry of a "dirk or dagger" (which includes fixed blades and locking folders with exposed, locked blades) is also prohibited under § 21310. This is a "wobbler" offense that can be charged as a misdemeanor (up to one year) or a felony in some circumstances.

California law does not require a jury to find intent to harm for a concealed dirk/dagger conviction (People v. Rubalcava, 2000). Simple knowing possession is sufficient.

Where You Can't Carry (Restricted Locations)

Even for knives that are otherwise legal to carry, California restricts them in several locations:

• Schools (K-12 and universities): Under § 626.10, all knives except non-locking folders with blades 2.5 inches or shorter are prohibited on school property. An exception exists for fixed blades over 2.5 inches at universities when used in or around a residence or for food preparation.
• State or local public buildings and meetings: Knives with blades over four inches that are fixed or capable of being fixed in an unguarded position are restricted (§ 171b).
• Airports and passenger vessel terminals: Same four-inch restriction applies, and box cutters are specifically prohibited (§ 171.5).
• Public transit sterile areas: Undetectable knives prohibited (§ 171.7).

Blade Length Restrictions

• Switchblades / automatic knives: Two-inch blade maximum for legal carry. Measured as total blade length including unsharpened portion.
• Schools: 2.5-inch blade maximum for non-locking folders.
• Public buildings, airports: Four-inch blade maximum for fixed or lockable blades.
• San Francisco: Any length switchblade is prohibited by city ordinance.
• Los Angeles: City ordinances impose additional carry restrictions on dirks and daggers.

Special Requirements

No permit system exists for carrying automatic knives in California. The law is binary — either your knife meets the size requirement or it doesn't. There's no license you can get that allows you to carry a larger automatic.

What About Assisted Openers?

Assisted-opening knives are explicitly legal under California's switchblade statute thanks to the bias-toward-closure exception in § 17235. This was a significant victory for the knife community. The In re: Gilbert R. (2012) court decision confirmed that the bias-toward-closure exception makes assisted openers legal.

However, assisted openers with locking blades are still subject to the dirk/dagger concealed carry rules if carried concealed with the blade in the locked-open position. Carry them closed in your pocket and you're fine.

If you want to carry a spring-assisted knife in California without legal risk, an assisted opener is the way to go. It gives you fast one-hand deployment without triggering the switchblade statute.

Preemption

California does not have statewide preemption for knives. Local cities and counties can — and do — pass their own knife ordinances. Notable examples:

• San Francisco: Prohibits switchblades of any blade length (stricter than state law's two-inch threshold)
• Los Angeles: Significant carry restrictions on dirks and daggers beyond state law
• Many other municipalities throughout the state have their own ordinances

This is a real problem for travelers. California's knife laws are already complex at the state level, and local variation makes compliance even harder. Always check the local ordinances for the specific city you're visiting.

Age Restrictions

California's switchblade statute (§ 21510) does not specify age-based restrictions — the prohibition applies to everyone. The sale/transfer restriction in § 21510(c) applies universally, not just to minors.

The school grounds restriction (§ 626.10) applies to all persons, not just students.

Buying Automatic Knives in California

This is where it gets tricky. § 21510(c) prohibits selling, offering for sale, loaning, transferring, or giving a switchblade with a blade two inches or longer. This applies to in-state sales.

The Federal Switchblade Act also restricts interstate shipment of automatic knives. Combined with California's state restrictions, purchasing a full-size automatic knife for carry in California isn't a viable path.

Automatic knives with blades under two inches can be legally purchased and carried. Assisted openers of any blade length can be purchased and carried (closed).

We do not ship automatic knives with blades two inches or longer to California addresses.

Frequently Asked Questions

Can I carry an OTF knife in California?

Only if the blade is under two inches. OTF knives with blades two inches or longer cannot be carried on your person, kept in your vehicle in public, or sold in California. Micro OTFs with sub-two-inch blades are legal.

Are switchblades illegal in California?

Switchblades with blades two inches or longer are illegal to carry, possess in a vehicle in public, or sell/transfer. Ownership at home is not explicitly prohibited. Switchblades with blades under two inches are legal. In San Francisco, switchblades of any length are prohibited by city ordinance.

Is there a blade length limit for automatic knives in California?

Yes. Two inches is the maximum blade length for a switchblade that can be legally carried or sold. This is the total blade length including unsharpened portions.

Recent Law Changes

California's switchblade laws have been relatively stable since the assisted-opener exception was added to § 17235. The People v. Castillolopez (2016) Supreme Court decision clarified that non-locking folders aren't dirks/daggers, which was a positive development. The State v. Hester (2020) decision, however, upheld a dirk/dagger conviction for box cutters with one-inch blades, confirming that there's no safe minimum blade length under the dirk/dagger statute.

No recent legislation has moved to relax California's switchblade restrictions, and given the state's general approach to weapons regulation, changes in a permissive direction are unlikely in the near term.

Legal Disclaimer

This article is for informational purposes only and does not constitute legal advice. Knife laws change — sometimes faster than websites update. Federal, state, and local laws may all apply to your situation, and local ordinances can be more restrictive than state law.

Before purchasing, carrying, or traveling with any automatic knife, OTF knife, or switchblade, verify current laws with official state and local sources. We are not attorneys, and we are not responsible for actions taken based on this information.

When in doubt, consult a licensed attorney in your jurisdiction.