In the village of Supai next to the store, and across from the Cafe. Full service inside. There is also a drop box outside.
MAILING GEAR or PERSONAL SUPPLIES to the Village (Its a NO NO)
This is not acceptable for Tourists/Visitors. Regardless of what you may have experienced in the past, or read written in books about the area.
Available at the Post Office and the Store. Advisable you carry some of your own in case they are out or the post office is closed for lunch, etc.
Available at the Camper/Tourist Check-in Office and the Store. You might want to carry some of your own.
Mule team. Too cool!
Mail post cards to yourself back home or to loved ones as you pass through the village. The postmark is unique since the village is one of two locations still delivering mail via pack animals. The other location is the Grand Canyon, down to Phantom Ranch.
Having cards mailed to yourself with the postmark canceling out the stamp is a wonderful memento or keepsake of your trip.
Its advisable that you bring your own cards and stamps in case they are sold out. There is a outside postal drop box on the post office.