Carry-On Banned Items: Rules by Category and Checkpoint

Check three separate things before packing: what the security checkpoint admits, what the airline can transport, and what you may possess or import. A security permission does not settle dangerous-goods acceptance, baggage allowance or customs. Repeat the check for another screening during transit and on the return trip. This guide covers key categories, not every product or jurisdiction.

Knives, scissors and other sharp items

A shorter blade does not automatically approve every knife. The dated TSA interpretation from October 2023 and the indexed public guidance phrase the exact four-inch scissors boundary differently; avoid relying on that boundary. The public TSA page was not fully accessible for this review, so its indexed excerpt is not a full current-page certification.

GOV.UK permits fixed-cartridge razors, sewing and knitting needles, tweezers and nail clippers. That does not approve loose blades, an open straight razor or every accessory in a complete kit. Check every part of a multi-tool. A sheath or original packaging does not change the category. See the separate scissors answer, knife rules and razor guidance.

Tools, sport and weapons

The EU list and GOV.UK work-tool table restrict dangerous tools including drills, saws and cutters, with category and blade or shaft criteria. There is no worldwide five-centimetre tool rule. Fuel, gas cartridges and batteries need a separate dangerous-goods check.

GOV.UK permits tennis rackets, fishing rods and billiard cues in both baggage categories, but excludes bats, golf clubs and other listed equipment from the cabin. Other countries can differ. Airline dimensions still apply. Do not assume every skateboard, rope or sporting object is prohibited just because it could strike someone.

Firearms, realistic replicas, bows, crossbows and arrows are cabin exclusions in the EU list. Check the exact firearm or replica category, legal permissions and airline acceptance before planning checked transport. UK source tables do not give a consistent blanket permission for every replica. Explosives, detonators and many pyrotechnic articles are excluded from both cabin and checked baggage; checking is not a universal alternative.

Liquids, food and medicines

Use the actual airport's container and bag procedure. GOV.UK says many airports retain 100 ml while some allow containers up to two litres. Container capacity, not merely the liquid left inside, matters where a capacity limit applies. Do not export a new airport limit to another checkpoint.

Creams, pastes and liquid foods can fall under liquid screening. This does not ban every solid food or every can. Medicines, baby food and duty-free have their own presentation and screening conditions. A prescription or original container does not approve every quantity, controlled medicine or destination import. Food import restrictions are separate as well. Do not try to avoid screening by wearing or concealing an item; ask the authority about the actual product.

Lithium batteries and installed devices

FAA does not impose a general maximum of one or two small personal-use spare lithium batteries. It does limit certain larger batteries, and airlines may be stricter, including for power banks. Determine Wh from the battery's rated voltage and capacity; a charger-output voltage is not a substitute. Do not pack a damaged or recalled battery likely to produce dangerous heat. Scooters and other large equipment need their actual airline and battery-category review.

FAA prefers portable electronic devices in the cabin. Installed and spare batteries are distinct; an accepted installed battery is not automatically banned from the hold merely because it is above 100 Wh. Vaping devices are a separate cabin/person-only category, protected against activation, with no onboard charging; FAA limits their batteries to 100 Wh lithium-ion or 2 g lithium-metal. Also check airline counts and destination restrictions.

Lighters, matches and dangerous products

Current FAA entries permit one ordinary lighter of an accepted type and one packet of safety matches in the cabin or on the person. Strike-anywhere matches and torch-flame lighters are prohibited. GOV.UK requires the single lighter to stay on the person throughout the flight in its specified bag, not back in hand luggage after security. Follow the applicable conditions; do not combine different countries' instructions or reuse an old lighter-case exception as current approval.

A 100 ml container does not make petrol, solvent, poison, corrosive chemicals or compressed gas acceptable. GOV.UK prohibits many dangerous chemicals in both baggage categories. FAA distinguishes certain personal toiletries under conditions from fuel, paints and other dangerous goods. Product names alone do not ban every nail polish, repellent, acrylic paint, candle or hand warmer. Ask the manufacturer for the safety data sheet if classification is unclear and confirm the exact product with the carrier. Do not test it yourself or move it to checked baggage to bypass a restriction.

Medical radioactive products and devices also have category-specific rules; FAA identifies certain implanted or administered medical exceptions. This is not approval of any medical isotope, package or destination import. Likewise, no general worldwide permission to check pepper spray or a stun device is established here.

Customs and a checkpoint refusal

Cash declarations, food, medicines, weapons, counterfeit goods and protected natural products follow destination and transit rules. There is no universal US-dollar declaration threshold or worldwide requirement to declare every laptop and piece of jewellery. Security approval is not import permission.

Inspect reused bags and pockets at home. If an item is refused, follow instructions and ask which options are available. Returning to check-in, mailing, storage, later return, free handling and the absence of sanctions are not guaranteed. Remove cabin-only items before any gate surrender. For permitted items that are simply awkward or unnecessary, use what not to pack.

Official sources and scope

Use the named jurisdiction and product category, not a worldwide permission.

• GOV.UK: baggage screening and lighter placement
• GOV.UK: chemicals and toxic substances
• GOV.UK: sporting equipment categories
• GOV.UK: ammunition and explosive articles
• FAA: spare lithium battery limits and protection
• FAA: devices with installed batteries
• FAA: permitted lighter types and exclusions
• FAA: safety matches and strike-anywhere exclusion
• GOV.UK: personal and sharp items
• GOV.UK: work tools and hold confirmation
• EU: prohibited article categories (official PDF)
• TSA: published 2023 interpretation (dated evidence)
• TSA: indexed public-guide excerpt only
• CATSA: sharp object screening categories
• FAA: dangerous goods, toiletries and medical exceptions
• GOV.UK: airport-specific liquid screening rules
• GOV.UK: electronic device screening
• CDC: medicine rules across destinations
• GOV.UK: essential medicines and equipment
• FAA: vaping devices and no onboard charging