We are not lawyers, this is not legal advice. Please check with a local attorney for the latest knife regulations in your local jurisdiction.
How do Knife Laws Work?
There are federal, state, and local laws regulating knives.
There is only one federal law regulating knives - the Switchblade Knife Act of 1958 and an amendment to the act in 2009. Federal knife law only applies those traveling from one to state to another, entering federal property (e.g. a military base), or live in Washington DC.
All 50 states have their own knife law, and many of the local jurisdictions within a state will oftentimes have their own, more regulated knife laws as well. For example, if you live in Seattle, Washington, you must follow Washington state’s knife laws as well as Seattle’s knife laws. If you travel to Olympia, Washington you must follow Olympia’s knife laws and during your 3 hour drive, you must also follow the knife laws of all the municipalities between Seattle and Olympia.
It gets even trickier. Laws are made by the legislative branch, and although tricky to read, are made publically available online. However, American judges also help create the law, in the sense that their decisions in a case becomes precedent for decisions in future cases.
There are over 19,000 municipalities in the United States. Tracking and maintaining a comprehensive, always up to date dictionary of knife laws is an incredibly daunting task, requiring significant resources.
To make this problem much worse, knife laws regulating possession do not require intent of a criminal action to be illegal. What this means is, it doesn’t matter if the knife you are carrying is very clearly used as a tool in a job or hobby, the difference between 3 inches and 3.1 inches, or the type of knife, could be thousands of dollars in court and lawyer fees, jail time, and a criminal record. This is a real problem, in fact, thousands of law abiding citizens in New York City are arrested every year for possessing a knife they bought over the counter from sporting goods and hardware stores in New York City.
For this reason, we are going to focus on the state laws and major U.S. cities to provide value to the most people with our finite resources.
If you want to stay safe, carry a multi-tool with a blade less than 2.5 inches. This is generally legal everywhere except in special areas such as schools, airports, government buildings, etc.
Knife Laws By State