Originally Posted by ESpen36

The Passport Card is intended for use by border community residents who frequently cross the northern or southern borders by land or sea. It also is intended for USC who go on cruises within the Caribbean Basin countries, the Bahamas, and/or Bermuda. But the Passport Card is not a global travel document, and it was never intended to be used for air travel. The Passport Card does not replace the Passport Book except in those limited circumstances I described above.

In fact, IMHO, residents of border communities would be far better off applying for NEXUS or SENTRI, since those programs offer dedicated lines at the border crossings (in addition to the "ReadyLane" program that is available to all other WHTI-compliant document holders as well).

I have a Passport Card that I use while traveling domestically so I don't risk losing my driver license (or exposing my home address to unscrupulous employees). I also have a NEXUS card. But in addition to these cards, I always travel with my Passport Book when flying, even when just hopping down to DCA on a commuter flight. You just never know when you might be rerouted through another country, or decide to take a last-minute trip, or have another need for the Passport Book!

In fact, although the NEXUS card is technically sufficient travel documentation in order to depart the USA by air, I remember being told at my initial NEXUS interview that I ALWAYS needed to have my passport with me as well, in case the officers asked to check it upon entry to Canada or the USA.

Remember, too, that major airlines also want to verify that you have proper documentation to enter the destination country, or else the airlines could face fines and the costs of repatriation. So, even though a NEXUS card might be sufficient for a USC to depart the USA by air, it is not sufficient to enter the EU/UK/CH by air, for example. So, the airline probably would not board you without making sure you were carrying your valid Passport Book.