Knife laws are set state by state, and the rules that catch people out aren't obvious: whether an automatic (switchblade) knife is even legal to own, whether you can carry a knife concealed, and — the sneaky one — whether a city can add its own rules on top of the state's. A knife that's legal at home can be a crime one state, or even one city, over. Below is where each state stands. Tap any state for the dated, officially-sourced detail. For the bigger picture, see laws you didn't know you were breaking.
Switchblades & automatic knives by state
Federal law (the 1958 Switchblade Act) only governs importing and selling automatic knives across state lines — everyday possession is set by your state. Most states now allow automatic knives outright; a few allow them with limits (blade length, or open-carry only); and about a dozen still restrict or ban them. "Legal" here means legal to own and generally carry; "Limited" means legal with restrictions; "Restricted or banned" means possession or carry is limited or a crime.
Carrying a knife concealed
Separate from whether a knife is legal to own, states limit carrying one concealed — usually by blade length, knife type, or intent. Every state lets you carry some knife, but roughly half attach conditions. "Broadly allowed" means concealed carry of ordinary knives is generally lawful; "Allowed with limits" means there are conditions worth checking before you carry.
The one that catches travelers: local preemption
This is the rule almost nobody checks. In a preemption state, one statewide knife law controls and a city can't add its own — what's legal in the state is legal everywhere in it. In the other states, a local ordinance can ban or restrict a knife that state law allows, so a blade that's fine across the state can still get you cited in a particular city (think large-city ordinances on blade length or "gravity knives"). If your destination is in the second group, check the city, not just the state.
Know it before you carry
This is a snapshot. LawLert pins the live knife rules to exactly where you are and alerts you when one changes or when you cross into a state where they flip. Browse all state laws.
FAQ
Are switchblades legal?
It depends entirely on the state. Most states now allow automatic (switchblade) knives outright, a handful allow them with limits (blade length, or open-carry only), and about a dozen still restrict or ban them. Federal law (the Switchblade Act) only governs import and interstate sale — day-to-day possession is set by your state, so a knife that's legal at home can be a crime one state over.
Does concealed carry apply to knives?
Yes. Separate from whether a knife is legal to own, many states limit carrying one concealed — by blade length, by knife type, or by intent. Every state lets you carry some knife, but roughly half attach conditions. Your state's page shows the specifics.
What is knife-law preemption and why does it matter?
In a preemption state, one statewide knife law controls and a city can't add its own rules. In the other states, a local ordinance can ban or restrict a knife that state law allows — so a blade that's legal across the state can still get you cited in a particular city. This is the single biggest way travelers get caught out.
How current is this?
Each state links to its detail page, which shows the official statute source and the date LawLert verified it. This hub is generated live from that same data.