I’m a long-time Nexus member, which is a program for expedited travel to and from Canada, which also gives me membership in TSA Precheck and Global Entry (expedited US customs at airports). If you are eligible, it is worth joining.
I am on reddit and I am part of the Global Entry, TSA, Nexus_TTP, and uscanaborder subreddits since I’ve learned a lot about these programs just through use.
A consistent problem which I have found along with a lot of other verified travelers is that a lot of agents and airline employees do not understand the Western Hemisphere Travel Initiative. Neither do they understand the required documents to go through TSA. I have gone through the government’s websites and here is a helpful table with the current rules as I can gather from looking through official government websites:
| TSA Precheck | Global Entry | Nexus | SENTRI | FAST | Passport card | Passport | Other Real ID | Non-Real ID | Viajero Confiable | Military ID or Merchant Mariners | American Indian card | |
| Domestic flight TSA | TRUE | TRUE | TRUE | TRUE | TRUE | TRUE | TRUE | TRUE | TRUE | TRUE | ||
| Land or sea border to US | TRUE | TRUE | TRUE | TRUE | TRUE | On official orders | TRUE | |||||
| International flight to US from anywhere | TRUE | |||||||||||
| Flight to US from Canada | TRUE | TRUE | On official orders | |||||||||
| Expedited TSA | TRUE | TRUE | TRUE | TRUE | ||||||||
| Expedited customs into US | TRUE | TRUE | TRUE | |||||||||
| Expedited customs into Canada | TRUE | |||||||||||
| Expedited customs into Mexico | with Viajero Confiable | with Viajero Confiable | with Viajero Confiable | with Viajero Confiable | TRUE | |||||||
| Flight into Canada from anywhere | TRUE | TRUE |
This is what I understand from reading through government websites outlining the rules. Yes, it’s a bit confusing but fortunately agents only need to know the row which is relevant to their job.
The long and the short of it is to get a Nexus card and then apply for Viajero Confiable if you plan on going to Mexico more than once. It’s the best program as is clearly seen in this table.