Illinois knife laws are complex and vary significantly depending on the type of knife, blade length, intent, and location. At the state level, most pocket knives and common folding knives are legal to own and carry, but there are important restrictions and exceptions to understand.
Switchblades and automatic knives are illegal to possess or carry in Illinois unless you are over 21 and have a valid Firearm Owner’s Identification (FOID) card. Even with a FOID card, local ordinances—such as those in Chicago—may still prohibit these knives entirely. Ballistic knives, which can propel a blade by mechanical means, are strictly prohibited statewide, regardless of FOID status.
Blade length is a key factor. Knives with blades shorter than 3 inches are generally legal to carry without a special permit. Carrying knives with blades 3 inches or longer is subject to stricter regulation, especially in public places or government buildings, where such knives are often banned outright. In Chicago, the law is even stricter, prohibiting the carry of any knife with a blade longer than 2.5 inches…