Knife laws in New Hampshire are among the most permissive in the country: you can own and carry any knife, of any blade length, openly or concealed, without a permit. The real legal risk is not what you carry but where you carry it and how you use it. Courthouses, schools, federal buildings, and airports are off-limits, convicted felons face separate restrictions, and brandishing a knife at someone can turn a legal everyday carry into a class B felony.
What You Can Own and Carry
Every type of knife is legal to own and carry in New Hampshire. RSA 159:16 currently prohibits only blackjacks, slungshots, and metallic knuckles; switchblades, stilettos, daggers, and dirk-knives were removed from that statute in 2010.1New Hampshire General Court. New Hampshire Revised Statutes Section 159:16 – Carrying or Selling Weapons Balisongs, gravity knives, automatic knives, machetes, large fixed-blade knives, and ordinary folders are all fair game.
There is no maximum blade length under state law. A two-inch folder and a 14-inch bowie knife are treated the same, and folding knives and fixed blades sit under identical rules.2American Knife and Tool Institute. New Hampshire Knife Laws
Carry rules are just as open. You can carry any knife openly or concealed, in a pocket, under clothing, in a bag, or on your belt, with no permit required. The 2010 revisions eliminated the earlier provisions that criminalized concealed carry of switchblades and similar knives.1New Hampshire General Court. New Hampshire Revised Statutes Section 159:16 – Carrying or Selling Weapons Blade type and length do not change the rules.
Cities and towns cannot add their own restrictions. RSA 159:26 gives the state sole authority over the sale, purchase, ownership, use, possession, and transportation of knives, so any stricter local ordinance is void. The one exception lets municipalities use zoning to regulate knife businesses the way they regulate other commercial enterprises.3New Hampshire General Court. New Hampshire Revised Statutes Section 159:26 – Firearms, Ammunition, and Knives; Authority of the State The rules in Manchester match those in Concord or any rural town. State preemption stops at the border, though, so a knife that is legal here may not be legal the moment you drive into Massachusetts.
Where You Still Can’t Bring a Knife
A handful of locations are off-limits no matter what the knife looks like, and the penalties for crossing those lines are serious.
Courthouses
RSA 159:19 prohibits carrying any deadly weapon, including knives, in a courtroom or an area used by a court. The ban covers both open and concealed carry. A violation is a class B felony, punishable by up to seven years in prison.4New Hampshire General Court. New Hampshire Code 159:19 – Courthouse Security5New Hampshire General Court. New Hampshire Revised Statutes Section 651:2 – Sentences and Limitations Courthouses enforce the rule with security screening, and you have to surrender any prohibited item before entering.
Schools
RSA Chapter 193-D restricts weapons on school property, school buses, and at school-sponsored events, at both public and private elementary and secondary schools.6New Hampshire General Court. New Hampshire Revised Statutes Section 193-D:1 – Definitions Penalties range from a class A misdemeanor, with up to a year in jail, to a felony depending on the circumstances. School disciplinary consequences, including suspension or expulsion, apply on top of any criminal charge.
Federal Buildings
Federal facilities in New Hampshire, including post offices and Social Security offices, fall under 18 U.S.C. § 930. Possessing a dangerous weapon in a federal building is a federal crime punishable by up to one year in prison, rising to five years if the weapon was brought in to commit another crime.7Office of the Law Revision Counsel. 18 USC 930 – Possession of Firearms and Dangerous Weapons in Federal Facilities
One exception matters for everyday carry: a pocket knife with a blade shorter than 2½ inches is excluded from the federal definition of “dangerous weapon” under this statute.7Office of the Law Revision Counsel. 18 USC 930 – Possession of Firearms and Dangerous Weapons in Federal Facilities A small folder in a post office is fine. A larger blade is a federal problem.
Airports
TSA rules prohibit all knives in carry-on baggage at commercial airports, regardless of type or blade length. Knives can go in checked luggage if sheathed or securely wrapped, and TSA officers have the final call at the checkpoint.8Transportation Security Administration. Knives
Private Property
Property owners and businesses can ban knives on their premises, and state law does not override that right. If you are told to leave or not enter because you are carrying a knife and you stay anyway, you can be charged with criminal trespass under RSA 635:2.9New Hampshire General Court. New Hampshire Revised Statutes Section 635:2 – Criminal Trespass Bars, event venues, and employers with weapons policies are the usual settings.
When a Legal Knife Becomes a Legal Problem
Any knife can become a “deadly weapon” based on how it is used. RSA 625:11 defines a deadly weapon as any firearm, knife, or other thing capable of producing death or serious bodily injury based on the manner it is used, intended to be used, or threatened to be used.10New Hampshire General Court. New Hampshire Revised Statutes Section 625:11 – General Definitions A kitchen knife in your bag is a kitchen knife. The same knife waved at someone during an argument is a deadly weapon, and that classification drives harsher penalties for assault, threatening, and related offenses.
Threatening Someone With a Knife
Under RSA 631:4, placing or attempting to place another person in fear of imminent bodily injury through physical conduct is criminal threatening. When a deadly weapon is involved, the charge jumps from a misdemeanor to a class B felony carrying up to seven years in prison.11New Hampshire General Court. New Hampshire Revised Statutes Section 631:4 – Criminal Threatening This is where most knife-related prosecutions in New Hampshire originate. Carrying is almost never the issue; behavior with the knife is.
Self-Defense
New Hampshire is a stand-your-ground state. Under RSA 627:4, you may use non-deadly force to defend yourself against imminent unlawful force, and deadly force only when you reasonably believe it is necessary. You have no duty to retreat if you are in your home, on its surrounding property, or anywhere you have a right to be, provided you were not the initial aggressor.12New Hampshire General Court. New Hampshire Revised Statutes Section 627:4 – Physical Force in Defense of a Person
Using a knife in self-defense is analyzed the same way as using any other deadly weapon. The deciding question is proportionality. Pulling a knife on someone shoving you in a parking lot looks very different from using a knife against someone swinging a baseball bat at you. The analysis is fact-specific, and getting it wrong can be the difference between a justified defense and a felony assault conviction.
Felons Face a Separate Rule
The main exception to New Hampshire’s permissive approach applies to anyone with a qualifying felony conviction. Under RSA 159:3, a person previously convicted of a felony against a person or property, a drug felony, or a controlled substance felony in any jurisdiction cannot possess a switchblade, stiletto, dagger, dirk-knife, or any other deadly weapon. A violation is a class B felony, up to seven years in prison, with confiscation of the weapon.13New Hampshire General Court. New Hampshire Revised Statutes Section 159:3 – Convicted Felons
The restriction reaches beyond the specifically named knives. The phrase “other deadly weapon as defined in RSA 625:11, V” sweeps in any knife used or intended to be used in a way capable of causing death or serious injury.10New Hampshire General Court. New Hampshire Revised Statutes Section 625:11 – General Definitions A covered felon carrying a large fixed-blade knife can be prosecuted even though the same knife is legal for anyone else.
Minors
New Hampshire has no minimum age for owning, possessing, or carrying a knife, and no state law restricts the sale or transfer of knives to minors.2American Knife and Tool Institute. New Hampshire Knife Laws Retailers may still require buyers to be 18, but that is store policy rather than law. School weapon policies apply regardless, so a teenager who can legally carry a pocket knife on the street will still be disciplined for bringing one on campus.
Penalties at a Glance
- Carrying a knife in a courthouse (RSA 159:19): class B felony, up to seven years in prison.4New Hampshire General Court. New Hampshire Code 159:19 – Courthouse Security
- Felon in possession (RSA 159:3): class B felony, up to seven years, plus confiscation.13New Hampshire General Court. New Hampshire Revised Statutes Section 159:3 – Convicted Felons
- Criminal threatening with a deadly weapon (RSA 631:4): class B felony, up to seven years.11New Hampshire General Court. New Hampshire Revised Statutes Section 631:4 – Criminal Threatening
- Weapon in a safe school zone (RSA 193-D): class A misdemeanor up to a felony depending on circumstances, with misdemeanor penalties of up to one year in jail.6New Hampshire General Court. New Hampshire Revised Statutes Section 193-D:1 – Definitions
- Federal building (18 U.S.C. § 930): up to one year in federal prison for simple possession, up to five years if the weapon was intended for use in a crime.7Office of the Law Revision Counsel. 18 USC 930 – Possession of Firearms and Dangerous Weapons in Federal Facilities
Law enforcement may also confiscate the knife in any of these cases, fines accompany most of the charges, and a felony conviction triggers the ongoing possession restrictions under RSA 159:3.