UK Legal Pocket Knives: 3 Inches or Less

A UK legal pocket knife has a cutting edge of 3 inches (7.62cm) or less. It also does not lock open. Both conditions apply together under section 139 of the Criminal Justice Act 1988 ^[1].

Meeting the length limit alone is not enough. A 6cm blade that locks open still needs a good reason to carry in public. This page checks 13 knives against both parts of the test using manufacturer or major-retailer specifications. It states the carry status for each. It explains why “UK legal” printed on a listing is a retailer’s shorthand, not a legal guarantee.

This guide answers the product-level question directly. It states the source for every figure. It covers how the knives were chosen, what to check before buying, and where even a fully legal knife still cannot go.

This guide covers the legal test, cutting edge versus blade length versus overall length, how this list was built, the product table, use cases, what to check before buying, and carrying responsibly.

What is the legal test for a UK legal pocket knife?

A folding knife qualifies for the automatic carry exemption only if its cutting edge is 3 inches (7.62cm) or less and it does not lock open. Both parts apply at once. Meeting one and not the other still requires a good reason to carry the knife in public.

Section 139(1) and (2) of the Criminal Justice Act 1988 make it an offence to have a bladed or sharply pointed article with you in a public place. The one exception is a folding pocketknife ^[1]. Section 139(3) narrows that exception further. The section still applies to, and therefore still catches, a folding pocketknife if its cutting edge exceeds 3 inches ^[1]. Courts treat a knife that locks open as failing the definition of a folding pocketknife altogether. A locking blade of 3 inches (7.62 cm) or less gets no exemption either.

gov.uk states the same two-part test in plain terms for buyers and sellers ^[2]. Full detail on the carrying offence itself, stop and search, and what happens if you forget a knife is in a bag sits on Can You Carry a Pocket Knife in the UK?

What is the difference between cutting edge, blade length and overall length?

Cutting edge is the only measurement that matters for the legal test. It is usually shorter than the blade length printed on a listing. Overall length includes the handle and is not a legal measurement at all.

Cutting edge runs along the sharpened part of the blade only. It runs from the point back to where the edge meets the handle or bolster. Many manufacturers list blade length in a way that sometimes includes an unsharpened ricasso or choil section near the handle. This makes blade length equal to or slightly longer than cutting edge. Overall length is the knife fully open, tip to butt. Closed length is the knife folded shut. Neither overall length nor closed length has any bearing on section 139.

A retailer that lists only “blade length” without a separate cutting-edge figure has not necessarily broken any rule. Do not assume blade length and cutting edge are identical. This page uses cutting edge whenever a spec sheet gives both figures. The product table states plainly whenever a spec sheet gives only blade length instead.

Is “UK legal” an official legal classification?

No. “UK legal” is a phrase retailers use to market a knife. It is not a status defined anywhere in the Criminal Justice Act 1988 or in gov.uk guidance. The only legal test is the one above: cutting edge and lock type, checked against section 139.

A retailer applying the phrase in good faith to a genuine non-locking, sub-7.62cm knife is describing the product accurately. The phrase itself still is not a legal guarantee. Nothing stops a listing from applying it loosely, measuring blade length instead of cutting edge, or omitting the lock type.

Check the cutting edge and lock type yourself against the product table below. Do not rely on a listing’s own label.

How we choose the knives on this page

Every entry here comes from a manufacturer specification page or a major UK or European retailer’s product page, fetched and checked on 2026-09-28. None come from hands-on testing. My Knife Guide does not test knives, invent reviews, or assign ratings.

This page uses cutting edge whenever a manufacturer states it separately from blade length. The product table and the statusNote for that item say so plainly whenever only blade length is given. Every entry links to its specSource so you can check the figure yourself. Lock type is checked the same way. Slipjoint, notch-joint and friction-fold mechanisms are recorded as non-locking. Any button, lever, ring or back-lock mechanism is recorded as locking.

Three knives on this page do not qualify for the carry exemption. They are included as contrast. This makes the difference between a slipjoint and a locking mechanism, and between a folding knife and a fixed blade, visible in one table rather than described in the abstract.

No entry on this page carries an affiliate link yet. A link added later will sit next to the specSource link, not replace it. It will be disclosed under the affiliate disclosure policy linked in the footer of every page.

Which UK legal knife suits which use?

Everyday carry, keyring use, outdoor work and traditional pocket use each favour a different size and handle, not a different legal test. The 7.62cm, non-locking rule applies equally to all of them.

A knife such as the Victorinox Spartan suits general everyday carry. It pairs a 6.2cm blade with scissors and a bottle opener. This suits parcels and packaging rather than heavy cutting. The Victorinox Classic SD and the Leatherman Micra suit keyring or bag carry where size matters most. Both sit under 4.1cm and add small tools such as tweezers or a file.

The Victorinox Pioneer Alox suits outdoor and light trade use. It adds a reamer and a stronger blade spine. The Spyderco UK Penknife was designed from the outset around this exact legal test. It adds a pocket clip for quick access. A small two-blade pattern such as the Case Peanut suits fishing and traditional pocket use. It keeps a short clip blade for line and a shorter pen blade for finer work. Anglers have carried this pattern for generations. Budget buyers checking the rule for the first time can consider a simple non-locking slipjoint. They should then verify its current specification before buying.

None of these use-case differences change the legal position. A 6cm blade used for parcels and a 6cm blade used for fishing line are both judged the same way under section 139.

Retail prices change often and are not listed here. A higher price does not create a stronger legal status.

What should you check before buying a UK legal pocket knife?

Check the lock type first, then the cutting edge figure, then how the blade opens. A listing that gets any of these three wrong changes the knife’s legal status, not just its marketing description.

Lock mechanism: confirm the specification states non-locking, slipjoint, or friction-fold. A listing that says “locking” or shows a liner lock, back-lock, button lock or Opinel-style ring lock means the knife needs a good reason to carry, whatever the blade length. Full detail on how UK law treats each lock type sits on Lock Knives and UK Law.

Check cutting edge, not blade length. A listing that gives only one figure states an upper estimate of the cutting edge. It is not a confirmed measurement. Opening mechanism: a thumb stud, nail nick, or Spyderco-style hole for one-handed opening does not affect legal status by itself. An assisted-opening mechanism and an automatic mechanism are both treated as a banned flick knife or gravity knife under the Restriction of Offensive Weapons Act 1959, regardless of blade length ^[4]. An assisted-opening mechanism uses a spring to complete the opening after a short manual push. An automatic mechanism uses a button to release the blade. Manual, unassisted opening by hand does not trigger this ban, whatever the mechanism used to start it.

A multitool knife blade is judged by the same lock-and-length test as a single blade. Full detail on Leatherman, Victorinox and other multitool brands sits on Multitools and Swiss Army Knives: UK Carry Rules.

A listing that gives you nothing but a marketing label and a photo is not enough. Go back to the primary source instead of trusting the label. gov.uk’s own buying and carrying guidance sets out the cutting-edge and lock test in the same terms used throughout this page. It costs nothing to check a product against it directly before paying for a knife described only as “UK legal” ^[2].

Buying any of these online adds a separate check on top of the cutting-edge and lock test: age verification at the point of sale and again at delivery. Full current detail on what a retailer must check and what that means for you as a buyer sits on Buying Knives Online in the UK: Age and ID Rules.

Where can you not carry a UK legal knife even though it is legal?

A folding pocketknife exempt under section 139 is not caught by section 139A merely because it is on school premises. Schools can still ban knives under their own rules. Courts and other venues can apply security and entry rules.

Section 139A makes it a separate offence to have an article to which section 139 applies, or an offensive weapon, on school or further education premises. The good-reason or lawful-authority defence applies to articles within its scope ^[3]. A non-locking folding pocketknife with a cutting edge of 3 inches (7.62 cm) or less falls outside that scope unless it is an offensive weapon. Courts, hospitals, airports, stadiums and licensed venues may refuse entry under their own security rules, regardless of the public-place exemption.

Self-defence does not change any of this. The Crown Prosecution Service states that carrying a weapon because of a general, ongoing fear of being attacked does not amount to a reasonable excuse or good reason ^[5]. Carry a knife for the task it is suited to, not as a response to a perceived threat.

This is legal information. It is not legal advice. Get advice from a solicitor or Citizens Advice for a specific situation.