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Can You Bring a Knife on a Plane? Rules by Departure

Knife rules differ by departure country and destination. Compare Canadian and UK screening, US restrictions, checked packing and prohibited types.

Sources and scope

Source-based research; no hands-on test or specialist review claimed.

  • Canadian small-blade exception excludes US flights and prohibited knife types.

    Departures screened by CATSA; page modified 2026-02-25

    Knives and other sharp objects; Prohibited Knives

    Source review: · Codex (AI source review)

  • Sharp/pointed knives are prohibited in UK hand luggage, independently of the 6 cm threshold.

    UK airport security

    Other personal items: Knife row

    Source review: · Codex (AI source review)

  • TSA pocket and utility knife classifications; limited cutlery exception.

    US TSA screening; official indexed listing accessed; individual item URL returned 403

    Pocket Knife; Swiss Army Knife; Utility Knives/Knife

    Source review: · Codex (AI source review)

A knife is not subject to one worldwide carry-on rule. Check every airport where you will pass security, the destination's possession/import rules, and the airline. A permission at your first checkpoint does not cover a connection.

Screening rules checked for this guide

Journey or authorityCarry-on position
Canada, domestic or international non-USCATSA permits certain knives with blades no longer than 6 cm; prohibited knife types remain excluded
Canada to the USCATSA prohibits knives of any type or length in carry-on
UK airportsGOV.UK excludes knives with a sharp or pointed blade and/or a blade longer than 6 cm
US TSA screeningPocket knives and utility knives belong in checked baggage; the TSA list describes a limited exception for plastic or round-bladed butter knives

Sources: CATSA sharp objects, UK personal items and TSA knife listings. The UK rule does not mean every blade shorter than 6 cm is allowed: the sharp/pointed condition matters too.

Checked baggage is not permission to possess a prohibited knife

CATSA identifies automatic-opening and concealed knife types as prohibited. Do not use the checked-bag column as permission to import or carry an illegal item. For an unusual knife or destination, obtain a decision from the relevant authority before packing.

Where carriage is permitted, sheath or securely wrap a sharp blade to protect baggage handlers and inspectors. Screening staff make the checkpoint decision; airline acceptance is a separate check.

A practical connection example

A traveller carrying a 5 cm knife from Canada to a non-US destination may meet CATSA's small-blade rule, yet still fail a later UK screening check if the blade is sharp or pointed. List each screening point before deciding where to pack it.

For multi-tools, identify the actual blade and mechanism rather than relying on a “travel-friendly” label. When the exact type or connection rule is unresolved, leave the item out until the authority confirms it. This guide covers the named authorities only and does not give a global legal clearance.

Frequently asked questions

Are all knives banned from carry-on everywhere?

No. CATSA permits certain blades up to 6 cm on Canadian domestic and non-US international flights, but not on flights to the US. UK and US rules differ.

Can every knife go in checked luggage?

No. Prohibited knife types, possession and import restrictions still apply. Confirm the exact item and destination before packing.

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Rules can change. Always verify with your airline before flying.