International Travel Packing Guide: TSA vs. Airline vs. Customs Rules
Three different sets of rules govern one trip abroad — knowing which one applies to your question saves a lot of confused searching.
Most packing questions blur together three completely separate authorities. TSA (or the equivalent security agency abroad) decides what can pass through the security checkpoint. Your airline decides what fits in your bag and what it costs. Customs decides what you're allowed to bring into a country. This site is built on TSA and FAA guidance, which answers the first question well — it doesn't yet cover customs rules for every country, and that's worth being upfront about rather than implying otherwise.
TSA: what's screened at security
This is what the rest of this site covers — whether an item can physically pass through the checkpoint, and whether it goes in carry-on or checked baggage. It's a security question, not a legal-ownership or import question. A pocket knife failing TSA screening doesn't mean it's illegal to own; it means it can't go through the checkpoint in your carry-on.
Airline: baggage size, weight, and fees
TSA doesn't set carry-on or checked-bag size and weight limits — that's entirely your airline's policy, and it varies by carrier, route, and sometimes fare class. This is a completely separate question from security screening, and it's the one most people actually mean when they ask "what can I bring."
Customs: what you can bring into a country
Customs authorities (CBP for arrivals into the US, and each destination country's own equivalent) regulate what can legally be imported — food, agricultural products, alcohol, currency over certain thresholds, and more. This is a completely different question from airport security, and the rules vary enormously by country. A solid cheese might pass TSA screening without a second look, while still being subject to customs food-import restrictions depending on where you're bringing it and from where.
FAQ
- If TSA allows an item, does that mean customs will too?
- Not necessarily — they're separate questions. TSA governs what passes airport security; customs governs what you're legally allowed to import into a country. An item can clear one and still be restricted by the other.
- Does this site cover customs rules for other countries?
- Not comprehensively yet — the catalog is built primarily on US TSA and FAA sourcing. For customs-specific questions, check the destination country's customs agency directly.