I'm not sure what the rules are; that's why I ask. As I said, I have returned from Cozumel through Hobby on SWA but I don't remember how it worked.
When we flew through Amsterdam to Warsaw our bags were checked all the way to our final destination. That was nice.
This site and several others all say the same thing.
It doesn’t matter whether you’re terminating your travel at that point, connecting domestically, or connecting internationally. All passengers have to clear immigration and customs at their first point of entry in the United States.
The United States is one of the only countries that doesn’t offer sterile international transit, which can be quite frustrating. In other words, even if you’re merely connecting in the United States between two international flights (like flying from Sao Paulo to New York to London) you still have to clear United States immigration, which means you’ll need a visa even for transit.
Clearing Immigration At US Airports: How It Works
Flying internationally to the United States? Here's what you should know about clearing immigration, checking bags, connecting flights, etc.
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