APO Zip Codes and the U.S. Military Postal Service

Soldier at desk writing a letter that will use the military APO zip code.

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The U.S. military uses the APO/FPO system to code mail for delivery to bases overseas. Army Post Office (APO) and Fleet Post Office (FPO) function much like standard zip codes do for mail delivery to any address.

Sending mail to servicemen and women overseas has been a time-honored tradition in the U.S. military since it began. Many a lonely soldier has been cheered up or kept in the loop about family events by a letter or care package from back home. 

The Tradition of Sending Mail to Troops

The tradition of sending mail to troops at war goes back hundreds of years, to the British Postal Service, and some evidence suggests it goes back even further than that, to ancient Egypt. In any case, sending mail and correspondence to troops stationed far from home is not a new concept. 

So it's sort of surprising that the Department of Defense created the U.S. Military Postal Service Agency as recently as 1980. The agency serves as the single military mail manager and is headquartered in Washington, D.C. Until its creation, each branch of the military and every government agency managed its own mail. 

This was done using the APO/FPO system, which is still part of the process but is now a lot more streamlined than it once was. Before mailing off that package, it helps to know how to navigate the APO/FPO addressing system, which allows anyone stateside to mail letters and parcels overseas to military members at domestic shipping rates.

Navigating APO and FPO Mail Deliveries

The U.S. Postal Service will deliver mail to a military port in the U.S. Then the Military Postal Service will transport mail intended for servicemembers at posts or aboard ships via military cargo aircraft. 

The suffixes after the APO or FPO address determine which Military Post Office will handle the package before it's sent overseas. For instance, AE indicates Armed Forces Europe, AA indicates Armed Forces Americas, and AP indicates Armed Forces Pacific. 

New Zip Codes for Overseas Action

When there's a major U.S. military action overseas, the Military Postal Service will often designate new geographic zip codes for U.S. military units and personnel in foreign countries. For instance, in 2003, the Military Postal Service assigned a slew of new APO zip codes for service members and civilian employees serving in Iraq.

The goal was to get mail from back home to personnel quickly and to improve postal service throughout the entire country of Iraq. So mail going to American troops stationed in Al Asad would go to zip code 09333, in Mosul, the code was 09334, Tikrit was 09393, and so on. 

Those zip codes were discontinued by the military in 2011 since American troops were returning home. 

APO Zip Codes Assigned to Units 

Often when there is an extended military operation overseas, units are moved around with little notice. For security purposes, rather than designate a zip code for a specific geographic location, the Military Post Office assigns a zip code to a particular unit or division. For instance, the 101st Airborne Division (Air Assault) had its own zip code, as did the 173rd Airborne Brigade.