UK knife laws are strict, and navigating them basically comes down to understanding the difference between what you can carry anywhere, anytime versus what requires a “good reason.”
While I appreciate this might be quite a contentious post, I believe all of us working in the outdoor industries should be carrying a small, legally acceptable pen knife.
I have carried a small knife for most of my adult life. My current EDC (Everyday Carry) is the Spyderco Squeak
Here is exactly how the law breaks down.
1. What You Can Carry Anywhere (Everyday Carry)
You are legally allowed to carry a pocket knife in a public place without needing a specific reason, but only if it meets two strict criteria simultaneously:
- It must be non-locking: The blade must fold freely at all times without any mechanical lock, button, spring, or catch holding it open (like a classic Swiss Army knife).
- The cutting edge must be 3 inches (7.62 cm) or less: This is measured along the actual sharp edge of the blade, not just the physical length of the metal.
Crucial Catch: “Lock knives” (where the blade locks open for safety) do not qualify as folding pocket knives under UK law, even if the blade is under 3 inches. Carrying one in public without a valid reason is illegal.
2. Knives You Can Carry ONLY with a “Good Reason”
If a knife has a blade longer than 3 inches, or if it has a locking mechanism (including most tactical knives, fixed blades, and many larger multi-tools), you can only carry it in public if you have a “good reason.”
Ultimately, a police officer or a court decides what counts as a valid excuse, but standard recognized examples include:
- Work: You are a chef taking your knives to a kitchen, or a carpet fitter, builder, or gardener who needs a utility knife for your trade.
- Religious Reasons: Such as the kirpan carried by orthodox Sikhs.
- National Costume: Such as the sgian-dubh worn with traditional Scottish Highland dress.
- Legitimate Outdoor Activities: You are actively traveling directly to or from a camping, fishing, or bushcraft activity where the knife is required.
What is NOT a good reason? Carrying a knife “just in case,” for general utility “just to be handy,” or for self-defense. In the UK, carrying any weapon for self-defense is strictly illegal. Furthermore, if you have a work knife, you must only transport it directly to and from work—stopping at a pub or shop on the way home with it in your pocket can get you arrested.
3. Knives That Are Completely Banned
Certain types of knives are completely illegal to own, bring into the UK, sell, possess at home, or carry anywhere. These include:
- Flick knives / Switchblades (knives that open automatically with a button or spring)
- Butterfly knives (Balisongs)
- Disguised knives (blades hidden in walking sticks, lipsticks, or belt buckles)
- Gravity knives
- Zombie-style knives and machetes (specifically blades over 8 inches with a sharp point and aggressive features like serrations, spikes, or multiple holes)
Summary of Legalities
| Knife Type | Legal to Own at Home? | Legal to Carry in Public? |
| Non-locking folding blade ≤ 3 inches | Yes | Yes (No reason needed) |
| Locking blade OR blade > 3 inches | Yes | Only with a “good reason” |
| Fixed-blade knife (any length) | Yes | Only with a “good reason” |
| Flick, Butterfly, or Zombie knife | No (Strictly banned) | No (Strictly banned) |
The maximum penalty for an adult caught carrying a knife illegally in public is 4 years in prison and an unlimited fine.