Knife Laws in Idaho

The declared purpose of knife law in the state of Idaho is to preserve the people’s right to keep and bear arms while imposing certain legal limits on concealed carry. Knife ownership is unlimited, in the sense that people can buy, sell, and possess any type of blade they wish, including such controversial items as martial arts throwing stars and ballistic knives.

Open carry of practically any knife is also allowed except in a few locations, such as schools, prisons, and some government buildings. Concealed carry rights are more limited, imposing a maximum blade length of 4”, or 2.5” for pocket knives on school property. Knives and cleavers used primarily for preparing food are exempted from the length rule.

Handily, most of Idaho’s relevant legislation for knife owners is encapsulated in Title 18, Chapter 33 of the Idaho Code, specifically sections § 18-3302, § 18-3302A, § 18-3302C, § 18-3302D, and § 18-3302E. These sections spell out almost the whole of legal material relating to knife law in Idaho. For the most part, the law is clear and straightforward, though a few vague areas remain.

Legality of Knife Possession

Adults (individuals 18 years old or older for purposes of knife law) can own, buy, or sell any kind of knife or bladed implement or weapon. There is no limit on actual possession, and the owner is naturally entitled to carry the knife while in their own home or on their property. This means that not only pocket knives and single-edged fixed knives such as Bowie knives and certain KA-BAR knives can be lawfully owned, but also double-edged blades such as daggers and swords.

Exotic knives including, but not limited to, balisong or butterfly knives, gravity knives, switchblades, ballistic knives, machetes, sword canes, undetectable knives, disguised blades, martial arts throwing stars, stilettos, folding knives with locking blades, and throwing knives are also legal to own in Idaho.

Adults may open carry any knife or blade in their possession anywhere except a handful of locations, such as courthouses, schools, prisons, government buildings, and nuclear power plants. Minors under 18 may only carry a knife or blade with the written permission of their parent or legal guardian, excepting pocket knives, and it is illegal to sell a minor under 18 such knives except with parental or guardian consent in writing. Minors under 12 years of age can only legally carry knives if their parent or guardian is physically accompanying them for the entire time the knife is under their control.

Knife Length Limit

Knives and blades of any length are legal both to own and to openly carry in the state of Idaho. Concealed carry allows a maximum blade length of 4”, which shrinks to 2.5” on school grounds or in a school. Since Idaho has no statewide preemption statute, towns, cities and counties are free to pass their own ordinances in this matter.

Concealed Carry of Knives

Idaho law is expressly written to strongly restrict the concealed carrying of knives and other blades. The law forbids concealed carrying of dirks, “dirk knives,” Bowie knives, and daggers, thus covering both single-edged and double-edged fixed blade knives. Knives with blades 4” in length or less are exempted, however, with no difference in legal treatment between fixed and folding blades.

The statute also exempts any knife, cleaver, or instrument intended mainly to prepare or eat food from the general concealed carry ban on basis of length. Proving intent is likely to prove difficult, however, unless the individual is a food service worker at their place of employment, or on their way to or from that location.

The state of Idaho imposes even more strict limits for concealed carry on school grounds or at schools. As described in § 18-3302D, all deadly and dangerous weapons are banned at these places. The law uses the federal definition, 18 USCS § 930, rather than the Idaho state definition of these weapons. This means only pocket knives with 2.5” or shorter blades are legal for concealed carried at schools.

Other Knife Law Considerations in Idaho

In spite of its lack of a preemption law, Idaho is highly knife-friendly, particularly in the areas of possession and open carry. Concealed carry is very limited, though with the odd exception noted of knives for preparing or eating food.

Carrying a knife in a car is a gray area. The knife is considered to be “carried” if it is within reach of any occupant of the vehicle, and “concealed” if it is not readily visible from outside the car. Though a few corner cases such as this exist, Idaho’s protections of knife ownership and open carry rights are robust enough to meet the purposes of most knife owners residing in or visiting the state.