The U.S. Army maintained an efficient postal system that helped keep soldiers connected with family and friends throughout their time at Camp Adair. GIs could send letters and postcards home free of charge through military mail, while packages could be mailed at regular postal rates. Many soldiers also used the postal service to send gifts purchased at the Post Exchange (PX) to parents, wives, girlfriends, and other loved ones. The post office also handled official postal business, including processing change-of-address requests whenever a soldier transferred to another unit or military installation.
To handle the enormous volume of mail generated by tens of thousands of soldiers, Camp Adair operated three post offices. The installation's main postal facility, which received all incoming and outgoing mail for the camp. From there, mail was sorted and distributed to the camp's two divisional post offices, one serving each side of the base. This well-organized system ensured that letters, packages, and official correspondence reached soldiers quickly, making mail one of the most important morale boosters during training. For many soldiers, receiving a letter from home provided encouragement, comfort, and a vital connection to the loved ones they were preparing to leave behind as they trained for overseas combat.