Diaries of TravelsTravel intelligence
  1. Home
  2. Answers
  3. Security & TSA
Security & TSAQuick reference

What can't you bring on a plane?

Quick answer

Never in carry-on: liquids over 100 ml, most knives and sharp tools, self-defense sprays, firearms and flammables. Never in checked bags: power banks, spare lithium batteries, e-cigarettes and lighters. Firearms fly only in locked checked cases, declared. Rules vary by country.

EditorialLast verified September 11, 2026

Two separate lists matter — what’s banned from the cabin, and what’s banned from the hold.

Not in carry-on:

  • Liquids, gels and aerosols over 100 ml (outside a few CT-scanner lanes).
  • Knives, blades, box cutters and most tools over a small size.
  • Pepper spray, tasers, and other self-defense weapons.
  • Flammables: lighter fluid, most aerosols beyond toiletries.
  • Firearms and ammunition.

Not in checked bags:

  • Power banks and spare (loose) lithium batteries — cabin only.
  • E-cigarettes and vapes — cabin only.
  • Lighters and matches (with narrow exceptions).

Special handling: firearms travel unloaded in a locked hard case in checked baggage, declared at check-in. Many countries ban items the US allows and vice versa.

Use our ‘Can I bring it?’ pages for the exact carry-on and checked status of 40 specific items, TSA-first with EU/UK notes.

Related questions

What is the 3-1-1 liquids rule?

Each liquid, gel or aerosol in your carry-on must be in a container of 3.4 oz (100 ml) or less, all fitting in one quart-size (1 litre) clear bag, one bag per passenger. Medications and baby food are exempt but may be inspected. Full answer →

Can I bring a power bank on a plane?

Yes, in carry-on only — never in checked bags. Up to 100 Wh (about 27,000 mAh) without approval; 100–160 Wh with airline approval; over 160 Wh not allowed. Some airlines now ban using or charging power banks in flight and require them within reach. Full answer →

Can you bring food through airport security?

Yes — solid food (sandwiches, fruit, snacks, chocolate) is fine in carry-on. Liquids and spreads (soup, yogurt, hummus, jam) fall under the 100 ml rule. Fresh produce and meat may be banned on arrival in another country. Full answer →

Rules change

Airline, airport and government rules change without notice. Treat this as a starting point and confirm with the airline or authority for your specific trip. Request a correction if something is out of date.