What Not to Pack in Your Carry-On: Prohibited and Ill-Advised Items

Most carry-on packing guides tell you what to bring. This one covers what to leave out — and why. Some items are prohibited outright by aviation security rules. Others are allowed by the rules but are genuinely bad ideas based on what can go wrong. Understanding both categories prevents confiscation at the checkpoint and protects you from real losses during travel.

Prohibited: Items That Will Be Confiscated

These items are not permitted in carry-on bags and will be taken by security if found. Checking them is the only alternative — and some cannot fly at all.

Sharp and bladed tools:

• Box cutters, Stanley knives, and utility knives of any size
• Scissors with blades longer than 6 cm (blade, not total length)
• Multi-tools that include a blade (the knife makes the whole tool prohibited)
• Hunting knives, penknives, and jack-knives
• Razor blades not in a cartridge (disposable razors with enclosed blades are allowed)

Liquids over 100 ml:

• Any liquid, gel, cream, or paste in a container larger than 100 ml — even if only partially full
• This includes: large shampoo bottles, full-size sunscreen, jar face cream, and peanut butter (classified as a gel)
• Marmite, Vegemite, hummus, and other paste-consistency spreads fall under the gel rule

Pressurized and flammable items:

• Camp stove fuel, lighter fluid, and CO2 canisters
• Large aerosol sprays (deodorant, dry shampoo) over 100 ml
• Paint spray cans
• Flammable liquids including some nail polish removers in large containers

Firearms and weapons:

• All firearms (these can be checked under strict declaration rules, but never carried on)
• Replica firearms and realistic toy guns
• Tasers and stun guns
• Martial arts weapons

Other prohibited items:

• Snow globes (the liquid base almost always exceeds 100 ml)
• Canned food (the can itself and any gel/liquid inside)
• Spare lithium batteries over 100 Wh (must be in carry-on, but very high-capacity ones are banned entirely)

Unexpected Items That Regularly Get Confiscated

These items surprise even experienced travellers:

• Snow globes — treated as a liquid regardless of the liquid volume inside the globe
• Jam, honey, and Nutella — jar-based products with a gel or liquid consistency
• Peanut butter — definitively classified as a gel by TSA and most airport security agencies
• Large candles in jars — the wax is not a concern, but gel candles are prohibited
• Corkscrew with a foil cutter blade — the blade makes it a prohibited sharp
• Baseball bats, golf clubs, and sporting bats — all must be checked
• Darts — the sharp tip makes them prohibited

Allowed But Ill-Advised: Items You Can Bring But Shouldn't

These items pass through security legally, but putting them in your carry-on creates real risk.

Irreplaceable documents in the original: Originals of birth certificates, marriage certificates, educational credentials, and legal documents should not travel in a carry-on — or ideally not travel at all. Bags get lost, gate-checked unexpectedly, or stolen. Scan everything and email the scans to yourself before you leave. Carry certified copies of genuinely required documents, never the irreplaceable originals.

All your cash in one place: Carrying your entire trip budget in your carry-on bag creates a single point of failure. If the bag is gate-checked unexpectedly, you cannot access it until arrival. If it is stolen, you have nothing. Split cash between a money belt worn on your body and a small amount in your bag. Keep a payment card as a third backup.

Jewelry you cannot afford to lose: Engagement rings, inherited pieces, and high-value jewelry are highest risk in a carry-on because the bag goes into the overhead bin, out of your sight and reach. Options: wear the jewelry on your person (it passes through security on a tray separately), use an anti-theft travel pouch worn under clothing, or leave irreplaceable pieces at home. Travel insurance covers documented valuables, but the claim process is stressful and reimbursement is rarely full value.

Breakable souvenirs without proper protection: Ceramic, glass, and similar fragile souvenirs packed loosely in a carry-on get broken by the pressure and movement of the overhead bin during flight. If you're buying breakable items, wrap them in clothing tightly, pack them in the center of the bag surrounded by soft items, and consider whether checked baggage is more appropriate for the return journey.

Extremely valuable items without documentation: High-end cameras, laptops, and other expensive electronics should travel in your carry-on — never in checked bags. However, photograph the serial numbers and model information before travel, and carry proof of pre-existing ownership if crossing international borders, particularly in regions where customs officials may question whether items were purchased duty-free at destination.

A Practical Pre-Security Mental Check

Before you leave for the airport, ask these questions:

1. Is there anything in this bag that I could not replace?
2. Is there anything sharp that I haven't thought about?
3. Are all liquids under 100 ml in their original containers?
4. If this bag were gate-checked and I couldn't access it for 6 hours, would I be fine?

A yes to the first two and a no to the fourth is your signal to repack before you leave home — not at the security bin.