A major change to US air travel rules is now in force. Since January 23, 2007, every passenger flying into the United States — American citizens included — must carry a valid passport. The days of re-entering the country on a birth certificate and a driver's licence are over for anyone arriving by plane.
The rule matters most for two groups. The first is US citizens who regularly hop across borders on holiday, especially to nearby destinations like Mexico or the Caribbean, where the lighter ID requirements were long the norm. If your passport expired years ago and you never bothered renewing it because you 'didn't need one', that loophole has now closed. Airport check-in staff will not wave you through with alternative documents, and being turned away at the gate is an expensive way to learn the new rules.
The second group is Americans living abroad. US citizens and their family members residing in Mexico without a current US passport are being urged to apply as soon as possible, either through the usual domestic application channels or via the US Embassy if they're already based there. Sorting paperwork from overseas is always slower than doing it at home, so the advice is simple: start the process now rather than when a family emergency or a flight booking forces the issue.
There's one notable exception. US permanent residents — green card holders — can continue using their valid green card in place of a passport when returning to the United States by air. If that's your situation, your existing document remains sufficient for re-entry, though carrying a passport is still worth considering for onward travel.
If you're planning a trip to Mexico and don't hold a passport, the practical takeaway is to apply immediately. Standard processing takes several weeks, and demand tends to spike when rules change, so leaving it until the week before departure is a gamble. First-time applicants need proof of citizenship, government-issued photo ID, a photo, and the application fee — details and forms are available through official State Department channels.
Why does this matter to travellers? Because document requirements are exactly the kind of detail that gets buried in the small print until it ruins a holiday. Airlines enforce these rules at check-in, not at the border, so a missing passport means being denied boarding — usually with no refund. Anyone with a Mexico trip on the books this year should check the expiry date on their passport today, not tomorrow. And if you're a green card holder, keep that card current and close at hand; it's now your ticket home by air.
