ATO

ATO may refer to:

• Abort to Orbit, an intact abort procedure for Space Shuttle launches
• Accumulated Time Off, a payroll term used to describe a method of accumulating paid or unpaid absence hours based on hours worked
• African Timber Organization, for sustainable forest management
• Air Tasking Order, (United States Air Force)
• Air Traffic Organization, an FAA terminology
• Air Training Officer, a former position at the United States Air Force Academy
• Air Transportation Office (Philippines), agency of the Philippine government
• Alpha Tau Omega, an American student fraternity
• Alpha Tau Omega (Philippines), a Filipino student fraternity
• Alpha Team Omega (United States) Subsidiary of Watching.I.Inc
• Alternative Trading Organization, an NGO focusing on Fair Trade exports
• Amiga Translators' Organization, an organization for translating Commodore Amiga applications
• Ammunition Technical Officer, a designation in the British Armed Forces
• Anti-Terrorism Officer, a position in the Homeland Security Community
• Arab Towns Organization, a network to promote cooperation between and development of Arab cities
• Assemble To Order, see configure-to-order
• Assisted take off
• ATO, the Amtrak station code for Atco (NJT station), New Jersey, U.S.A.
• ATO Records, a record label
• Atmos Energy Corporation's ticker symbol on the New York Stock Exchange
• Australian Taxation Office, the Australian government tax agency
• Authority to Operate, U.S. Government's final approval for a system or program to operate in a given environment
• Automatic train operation
• Hockey contracts, Amateur Try-Out in ice hockey.
• Chemotherapy, Arsenic trioxide a potent chemotherapeutic agent for acute promyelocytyc leukemia

Ato may refer to:

• A cacodemon of the Enochian angels
• Ato, Yamaguchi – a Japanese town
• Osman Ali Atto also written Osman Ali Ato, a Somali warlord
• One of three 2002 Football World Cup mascots