Base Exchange A Base Exchange ( BX ) ( US Air Force terminology : also referred to as a Post Exchange ( PX ) on Army posts , Navy Exchange ( NEX ) on Navy installations , Marine Corps Exchange ( MCX ) on Marine Corps installations and Coast Guard Exchange ( CGX ) on Coast Guard installations ) is a type of retail store operating on United States military installations worldwide . Originally akin to trading posts , they now resemble department stores or strip malls . Over the next few years , every exchange operated by the Army and Air Force Exchange Service will be rebranded simply as an Exchange ( X ) to simplify differentiation between the similar sounding BX and PX names . Service organization . Exchanges on Army and Air Force installations are operated by the Army and Air Force Exchange Service ( AAFES ) , while those on Navy bases are operated by the Navy Exchange Service Command ( NEXCOM ) , and those on Marine Corps installations are part of Marine Corps Community Services ( MCCS ) , which also runs the rest of Marine MWR operations . The Coast Guard Exchange ( CGX ) operates a handful of stores on Coast Guard installations . Exchanges on joint installations are generally served by the exchanges already operating upon the joining of the existing installations , though some smaller exchanges may close when they can no longer benefit the installation . Operations . Exchanges sell consumer goods and services to active duty , Reserve , National Guard , retired members of United States Uniformed Services and their dependents . Authority to use these facilities is normally determined by presentation of the individual ' s military member or military family member identification ( ID ) card , either when entering the store or when paying for goods and services . At many overseas locations Exchange privileges are determined as part of the local Status of Forces Agreement . Shopping privileges are also generally extended in overseas locations to U . S . Government civilian employees and their dependents who are assigned overseas . Shopping privileges can vary overseas according to applicable status - of - forces agreements with host nations . A typical exchange is similar to a department store , but other services such as military clothing sales / uniform shops , barber shops , hair care , beauty , laundry / dry cleaning , gas stations , fast food outlets , convenience stores ( " Shoppettes " or " Mini Marts " ) , beer and wine sales , liquor stores ( " Class Six " or " Package Stores " ) , lawn and garden shops , movie theaters and even vehicle maintenance and repair services are commonly available . Most ( but not all ) sales by exchanges are free of state and local sales or VAT taxes as the sales take place on U . S . military reservations ( exceptions include gasoline sales in the U . S . and sales by concessionaires licensed by the exchange ) . Unlike commissaries ( military grocery stores ) , exchanges , for the most part , do not receive significant appropriations from the federal government and must operate on a for - profit basis . With the exception of military personnel assigned to duty with the exchange services , exchange service employees ' salaries are paid from revenues generated from sales of merchandise , except for annual raises from funds appropriated by Congress . Exchanges are deemed Category C non - appropriated fund ( NAF ) activities , meaning they are designed to not only be self - sufficient , but generate a profit . Of course , exchanges are normally located on military reservations and , as a result , do not pay rent or tax for the use of land . Exchanges ' tax - exempt status ( as instrumentalities of the U . S . Government ) also reduces certain operating expenses . While exchanges must pay for the cost of transporting goods within the continental United States , Congress appropriates funds to subsidize the transportation costs of American merchandise to overseas exchange locations so that such items are available and affordable to personnel stationed overseas . Exchanges play an important role for U . S . military and Government personnel assigned overseas as they are often the only local source for American retail merchandise , such as clothing , electronics , books and magazines , fast food , etc . Exchanges also supply gasoline at prices roughly approximating those in the U . S . , normally on a rationed basis , to overseas personnel for personal use , since fuel prices in most foreign countries ( where U . S . military are stationed ) are normally much higher due to local taxes . Overseas exchanges also sell new North American - made vehicles to assigned personnel in cooperation with the " Big Three " automakers ( General Motors , Ford and Chrysler ) and Harley - Davidson motorcycles . AAFES and NEX have also established smaller field exchanges to provide military personnel with comforts and everyday items while deployed , even in combat zones such as Iraq and Afghanistan . NEX also operates small exchanges , known as " ship ' s stores , " onboard seagoing vessels . They are managed and operated by sailors in the Ship ' s Serviceman rating . Most profits earned by the exchange services , after paying operating expenses , are used to support community activities aimed at improving morale among service members and their families .