ATO

ATO may refer to:

Technology

 * Abort to Orbit, an intact abort procedure for Space Shuttle launches
 * Arsenic trioxide a potent chemotherapeutic agent for acute promyelocytic leukemia
 * ATO fuse
 * Automatic train operation
 * Assisted take off

Military

 * Air Tasking Order, (United States Air Force)
 * Air Training Officer, a former position at the United States Air Force Academy
 * Ammunition Technical Officer, a designation in the British Armed Force
 * Anti-Terrorist Operation in Ukraine, the Ukrainian government's operation in the war in Donbas, 2014-current time, since 2018 it has been called Joint Forces Operation.
 * ATO zone, the official name for territory where the war in Donbas takes place
 * A US Navy hull classification symbol: Fleet tug, old (ATO)

Organizations

 * Alpha Tau Omega, an American student fraternity
 * Alpha Tau Omega (Philippines), a Filipino student fraternity
 * Alternative Trading Organization, an NGO focusing on Fair Trade exports
 * Air Traffic Organization, a division of the Federal Aviation Administration
 * Air Transportation Office (Philippines), agency of the Philippine government
 * Arab Towns Organization, a network to promote cooperation between and development of Arab cities
 * ATO Records, a record label
 * Australian Taxation Office, the Australian government tax agency

Other

 * Ato, another name for dap-ay, traditional meeting places of various ethnic groups in the northern Philippines
 * Account takeover, a form of payments and online fraud
 * Assemble To Order, see build to order
 * Asset turnover
 * ATO, the Amtrak station code for Atco (NJT station), New Jersey, U.S.A.
 * Atmos Energy Corporation's ticker symbol on the New York Stock Exchange
 * Authority to Operate, part of a Risk Management Framework
 * Amateur Try-Out, a type of ice hockey contract

Places

 * Ato, Yamaguchi – a Japanese town
 * Ato Station