Knife Carry Laws: What You Need to Know
By Jason R. Caldwell – Tactical Gear Contributor, based in Bozeman, Montana
This is the 19th blog of the Knife blog series. You can check the other blogs I wrote from here – https://thriftyknife.com/blogs
Understanding knife carry laws is crucial whether you’re a collector, outdoor enthusiast, or everyday carrier. With different rules in each state — and sometimes even each city — knowing what’s legal can save you serious trouble.
Why Knowing Knife Laws Matters 
Knife laws are complex and vary widely across the U.S. What’s perfectly legal in Montana could be illegal in California. You need to know:
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Where your knife is allowed
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What types are legal to carry
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How blade length can affect legality
This blog aims to simplify those key points, especially for folks who love blades as much as I do.
Types of Knives Often Regulated 
Before diving into laws, here are some common knives that are often restricted or regulated:
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Switchblades/automatic knives
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Gravity knives
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Butterfly knives
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Fixed-blade knives (especially concealed ones)
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Folding knives with long blades
Key Legal Concepts to Know
1. Open Carry vs. Concealed Carry
Some states allow large knives if they’re visible (open carry), but not concealed. Others have no restrictions. Know your local stance.
2. Blade Length Limits
Often, the magic number is 3″ to 4″. If your blade is longer than local limits, it might be illegal — even if it’s a pocketknife.
3. Intent and Location Laws
Carrying a knife for self-defense? That can legally backfire. Many laws only allow knives for utility, work, or sport. Also, public buildings, schools, and government properties usually ban knives outright.
State-by-State Resources for Knife Laws 
Instead of guessing, use a trusted database to look up your specific state’s rules:
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AKTI State Knife Laws – Maintained by the American Knife & Tool Institute
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Knife Rights Legal Blade App – A mobile app that offers quick, state-by-state legality summaries
These links are helpful for staying up to date, especially when traveling.
Personal Experience: Why I Double-Check Laws When Traveling 
Years ago, I was traveling from Montana to New York. What’s legal in Big Sky Country didn’t fly in NYC — a 4-inch folding knife nearly got me fined. Since then, I always double-check laws using the resources above.
Even if you’re just crossing a state line, being informed is your best defense.
Knives That Keep You Legal (and Sharp)
At www.thriftyknife.com, we carry a wide range of folding knives and EDC tools that are compact and discreet — many of which fall within most legal blade length limits. If you’re unsure, feel free to contact us and we’ll help guide your choice based on practical use.
Our goal is to equip you legally and reliably — not just stylishly.
Final Thoughts on Knife Law Awareness 
Knife carry laws aren’t always easy to understand, but they’re critical for anyone who loves blades. Whether you’re a craftsman, chef, or survivalist, legal awareness is just as important as blade sharpness.
Questions? Confused about a specific state law? Drop a comment below and I’ll do my best to help out.
Also, what would you like to learn about in next week’s blog? Maybe we dive into the pros and cons of fixed blades vs. folders — or explore blade finishes? Let me know!