Why do I need a Passport to go to Rosarito?
If you plan on taking the shuttle that is included with your package you WILL need a Valid Government-Issued Passport to get across the border. Because you will be on a charter bus the same immigration laws required for a flight will apply here. Make sure to bring your physical Passport as you will have to fill out an immigration card when crossing the border.
The reason why we suggest people take their U.S. Passport and not a U.S. Passcard is to reduce any issues with re-entering the United States. The JusCollege position is that whatever issue may arise with a traveller returning to the United States via a land crossing, the likelihood of a delay is reduced by traveling with a Passport and not a Passcard. As the former carries the highest level of international legality.