STO may refer to:
Businesses and organizations Government NATO Science and Technology Organization Service du travail obligatoire, French men & women between certain ages deported to Germany during WWII to work as slave labour Sojourner Truth Organization, a defunct American leftist group Sovet Truda i Oborony (Совет труда и обороны): Council of Labor and Defense, a Soviet central planning agency of the 1920s United States Air Force Special Tactics Officer
Non-governmental organizations State Trading Organization, a publicly owned Maldivian company Statoil, a publicly traded Norwegian oil company
Science and technology Semi-automatic train operation Slater-type orbital, atomic orbitals STO-nG basis sets, of orbitals
Sports Space Tornado Ogawa, a professional wrestling throw SportsTime Ohio, a regional sports network in northeast Ohio, United States
Arts and entertainment Soldiers of the One, a group in the TV series Caprica Star Trek Online, a massively multiplayer online role-playing game STO, a posture emoticon used for representing a great admiration or great despair, see Emoticon#Orz Sto, pen name of illustrator Sergio Tofano
Transport Société de transport de l'Outaouais, a public transit operator in Gatineau, Quebec, Canada STO, the National Rail station code for South Tottenham railway station, London, England The airports of Stockholm, Sweden, by IATA code
Other uses Safe Torque Off, an electronic signal used in industrial drives for safety function Security through obscurity, a practice in security engineering Security token offering, a type of public offering in which tokenized digital securities, are sold in cryptocurrency exchanges Stø, a village in Norway Stoney language (ISO 639-3 code) STO (professional wrestling), a maneuver in professional wrestling
See also STOS (disambiguation)