UK Knife Law — What You Can Legally Carry Outdoors in Britain

The Basics

UK knife law catches people out more than almost any other outdoor regulation. There's a lot of misinformation floating around forums and social media, so let's set the record straight with what the law actually says.

The key legislation is the Criminal Justice Act 1988, Section 139, which makes it an offence to carry a bladed or pointed article in a public place without good reason or lawful authority. The Offensive Weapons Act 2019 updated and tightened several provisions.

But here's the important bit — there's a built-in exception for folding knives.

The Folding Knife Exception

You can legally carry a folding pocketknife in public without needing any reason at all, provided it meets both of these criteria:

1. The blade is 3 inches (7.62 cm) or less in length
2. The blade is non-locking — it folds freely without a mechanism that holds it open

That's it. A classic Swiss Army Knife with a short blade? Fine. A small Opinel with a twist-lock? That's a locking knife — you'd need a reasonable excuse.

What Counts as a Reasonable Excuse?

If you're carrying anything that doesn't meet the folding knife exception — a lock knife, a fixed blade, a bushcraft knife, a multitool with a locking blade — you need a "reasonable excuse."

The law doesn't give an exhaustive list, but here's what's generally accepted:

• Outdoor activities: Hiking, camping, bushcraft, fishing, and similar activities. If you're heading to the woods with a Mora bushcraft knife, that's a reasonable excuse.
• Work: Chefs carrying knives to work, carpet fitters, electricians, etc.
• Religious reasons: The Sikh kirpan, for example.
• National costume: The Scottish sgian-dubh worn with a kilt.
• Moving house or transporting knives: Taking a new knife home from a shop, or moving kitchen knives during a house move.

What's not a reasonable excuse:

• "I carry it for self-defence." This is explicitly not a valid reason. Ever.
• "I forgot it was in my bag." This is very weak and courts have rejected it repeatedly.
• "I always carry one." Habit is not a reasonable excuse.

The Journey Matters

Your reasonable excuse needs to match what you're actually doing. Walking through town with a fixed blade on your belt because you're "on your way to go camping" is a stretch if you're popping into Wetherspoons. The closer you are to the activity, the stronger your excuse.

Lock Knives — The Big Misunderstanding

This trips up more people than anything else. Lock knives are not folding knives under UK law, even though they physically fold. The legal definition of a folding knife for the purposes of the Section 139 exception requires the blade to fold freely — a locking mechanism disqualifies it.

This means:

• Liner lock knives — need a reasonable excuse
• Frame lock knives — need a reasonable excuse
• Back lock knives — need a reasonable excuse
• Axis lock knives — need a reasonable excuse
• Opinels with the twist ring — need a reasonable excuse

The case that settled this was Harris v DPP [1993], which confirmed that a lock knife is not a "folding pocketknife" for the purposes of the Act.

Banned Knives

Some knives are prohibited entirely under the Criminal Justice Act 1988 (Offensive Weapons) Order and the Offensive Weapons Act 2019. You cannot carry, buy, sell, or import these:

• Butterfly knives (balisongs)
• Disguised knives (belt buckle knives, comb knives, etc.)
• Flick knives / switchblades (blades that open automatically by a button, spring, or gravity)
• Zombie knives and zombie-style weapons
• Cyclone knives
• Push daggers
• Curved swords (with some antique exceptions)

Possession of these — even at home in some cases — can be a criminal offence.

Multitools

Multitools are judged by the same rules as any other bladed article. The question is whether the blade locks.

• Victorinox Swiss Army Knives (most models): Non-locking blades under 3 inches — legal to carry without a reason.
• Leatherman multitools (most models): Locking blades — you need a reasonable excuse.
• Gerber multitools: Check the specific model. Many have locking blades.

If your multitool has a locking blade, it doesn't matter that it also has a bottle opener and a screwdriver. The blade is what matters.

Fixed Blade Knives

Fixed blade knives — including bushcraft knives, mora knives, hunting knives, and kitchen knives — always require a reasonable excuse to carry in a public place. There's no size-based exception for fixed blades.

For outdoor use, this is rarely a problem. If you're heading out for a day of bushcraft or camping, carrying an appropriate fixed blade is perfectly reasonable. The key word is "appropriate" — a small bushcraft knife is much easier to justify than a 12-inch Bowie knife.

What Happens If You Get It Wrong?

If you're stopped and found to be carrying a knife without a reasonable excuse, you could face:

• A fine — potentially unlimited for adults
• Up to 4 years in prison for carrying a blade in a public place
• A criminal record — which affects travel, employment, and more

For banned weapons, the penalties are even more severe. Possession of a prohibited weapon can carry a sentence of up to 4 years.

In practice, police use discretion. A rambler with a Mora in their pack is going to get a very different response from someone carrying a lock knife in a nightclub. But "the police will probably be reasonable about it" is not a legal strategy.

Scotland

Scottish knife law is broadly similar to England and Wales but is covered under the Criminal Law (Consolidation) (Scotland) Act 1995, Section 49. The same basic principles apply — non-locking folding knives under 3 inches are exempt, everything else needs a reasonable excuse.

Practical Tips for Outdoor Enthusiasts

1. Choose the right knife for the activity. A small bushcraft knife is all you need for most outdoor tasks.
2. Keep it packed away during transport. Knife in the bag until you're at your campsite or in the woods.
3. Don't carry more than you need. One appropriate knife is easier to justify than a collection.
4. Be polite and cooperative if asked. If a police officer asks about your knife, calmly explain what you're doing. Most interactions end there.
5. Know your knife. Understand whether your blade locks, its length, and which legal category it falls into.

Recommended Legal Carry Knives

If you want a knife you can carry every day without worrying about the law, these are solid choices. Both meet the folding, non-locking, under-3-inch requirements.

Further Reading

For more on related outdoor law topics, see our UK outdoor law overview and our guide to trespass law.