Illegal Knives in Pennsylvania: Switchblades, Locations, and Penalties

Very few knives are illegal in Pennsylvania based on what they are. State law bans a narrow category of weapons designed to inflict serious injury with no everyday use, and the clearest example is the ballistic knife. Pocket knives, hunting knives, kitchen knives, and utility blades are all legal to own and carry. What trips people up is the rest of the picture: a perfectly legal knife can become the basis for a criminal charge because of where you carry it, who you sell it to, or what a prosecutor can prove about your intentions.

Which Knives Are Banned by Type

Pennsylvania’s prohibited-weapons statute, 18 Pa.C.S. § 908, makes it a first-degree misdemeanor to possess, sell, repair, or deal in any “offensive weapon.”¹ The statute does not list banned knives by name. It targets any implement designed to inflict serious bodily injury that serves no common lawful purpose. Most ordinary knives clear that bar without difficulty, since pocket knives, fixed-blade hunting knives, kitchen knives, and utility blades all have obvious legitimate uses.

The clearest knife that fails the common-lawful-purpose test is the ballistic knife, which has a detachable blade propelled by a spring mechanism. These are illegal under Pennsylvania law and under a separate federal statute that carries penalties of up to ten years in prison.²

Double-edged daggers occupy a grayer zone. Pennsylvania does not name daggers as prohibited, but a knife whose only function is stabbing has a harder time qualifying as having a common lawful purpose. Courts evaluate this case by case, and a knife’s design, marketing, and how you carry it all factor in.

Switchblades Are Now Legal

For decades, Pennsylvania grouped automatic knives, including switchblades, with prohibited offensive weapons. That changed when the legislature passed HB 1929, which took effect in early 2023 and removed automatic knives from § 908.¹ You can now legally buy, own, and carry a switchblade anywhere in the state, subject to the same restrictions that apply to any other knife.

One federal catch is worth knowing. The Federal Switchblade Act still prohibits shipping or transporting switchblades across state lines through interstate commerce, with exceptions for military members, law enforcement, and certain one-handed users.³ Enforcement against individual buyers is rare, but if you’re ordering from an out-of-state retailer, the technicality exists.

When a Legal Knife Becomes Illegal

This is where most people get caught. Under 18 Pa.C.S. § 907, possessing any “instrument of crime” with intent to use it criminally is a first-degree misdemeanor. The statute is indifferent to what kind of knife you have. A Swiss Army knife carried with intent to threaten someone is an instrument of crime. The same knife carried to open boxes at work is completely legal.

Pennsylvania draws no distinction between open carry and concealed carry of knives. There is no statewide blade-length limit and no requirement that a knife be visible. What separates lawful carry from criminal possession is provable intent, and context does the heavy lifting. A large fixed-blade knife sheathed on your belt during a camping trip looks very different from the same knife tucked in your waistband at a bar at 2 a.m.

Places Where No Knife Is Allowed

Some locations override every other consideration. Your intent does not matter, and neither does the type of knife.

Schools

Under 18 Pa.C.S. § 912, possessing any weapon on school property is a criminal offense, and the statute defines “weapon” broadly to include any knife or cutting instrument. The prohibition covers school buildings, grounds, and school transportation.⁴ It applies to public and private schools, kindergarten through twelfth grade. A small pocket knife forgotten in a backpack qualifies, and “I forgot” rarely holds up as a defense.

Courthouses

Under 18 Pa.C.S. § 913, knowingly possessing a dangerous weapon in a court facility is illegal.⁵ Most courthouses screen at entry. Some counties offer a check-in procedure so you can surrender a knife and retrieve it on your way out, but that practice varies.

Federal Buildings and Post Offices

Under 18 U.S.C. § 930, carrying a dangerous weapon into any federal facility is a federal offense. The statute carves out one exception: a pocket knife with a blade shorter than 2½ inches.⁶ Any blade at or above that length counts as a dangerous weapon for federal purposes. Federal court facilities are stricter still, with no pocket-knife exception.

Post offices are the strictest. Federal regulations ban carrying any dangerous or deadly weapon on postal property, openly or concealed, with no blade-length exception at all.⁷

Philadelphia and Local Ordinances

Pennsylvania has no statewide preemption law for knives, which means cities, boroughs, and townships can pass their own restrictions that go beyond state law. Philadelphia is the biggest example. A longstanding city ordinance broadly prohibits carrying cutting weapons on public streets and public property without a lawful reason such as work or recreation. The definition of “cutting weapon” is expansive and covers essentially any knife or razor.

The practical result: a knife that’s legal to carry openly in a rural county can get you cited in Philadelphia if you can’t articulate a legitimate reason for having it. State law will not protect you from stricter local rules, so checking the local code matters in any municipality you regularly pass through.

Selling or Transferring Knives to Minors

Pennsylvania prohibits selling or transferring a “deadly weapon” to anyone under 18. A knife designed as a weapon and capable of causing death or serious bodily injury falls within that definition. The restriction runs against the seller or transferor, not the minor. A teenager who receives a hunting knife from a parent for outdoor use isn’t automatically committing a crime, but a retailer who sells a combat knife to a 16-year-old is potentially on the hook. The school-property prohibition under § 912 applies to every student regardless of age.⁴

Penalties for Knife Offenses

Most knife-related charges in Pennsylvania are first-degree misdemeanors, which carry a statutory maximum of five years in prison, plus fines.⁸ The specific offense determines the exposure:

Possessing a prohibited offensive weapon under § 908 is a first-degree misdemeanor, up to five years in prison.¹
Possessing an instrument of crime under § 907 is a first-degree misdemeanor, up to five years in prison.
Bringing a weapon onto school property under § 912 is a criminal offense with potential imprisonment and fines.⁴
Bringing a weapon into a court facility under § 913 carries criminal penalties that vary by weapon type.⁵
Possessing a ballistic knife under 15 U.S.C. § 1245 carries up to ten years in federal prison.²

Five years is the statutory ceiling, not the going rate for a first offense. Prosecutors do bring these charges, though, particularly when a knife shows up alongside an assault or robbery and the weapons count gets stacked on top of the underlying offense. A conviction also produces a criminal record that can follow you into employment, professional licensing, and firearm rights.

1
Pennsylvania General Assembly. Pennsylvania Code Title 18 – Section 908
2
Office of the Law Revision Counsel. 15 U.S. Code 1245 – Ballistic Knives
3
Office of the Law Revision Counsel. 15 U.S. Code 1241 – Definitions
4
Pennsylvania General Assembly. Pennsylvania Code Title 18 – Section 912
5
Pennsylvania General Assembly. Pennsylvania Code Title 18 – Section 913
6
Office of the Law Revision Counsel. 18 U.S. Code 930 – Possession of Firearms and Dangerous Weapons in Federal Facilities
7
eCFR. 39 CFR 232.1 – Conduct on Postal Property
8
Pennsylvania General Assembly. Pennsylvania Code Title 18 – Section 1104