- ZTO stands for Zeta Tau Omega (sorority; est. 1999)
- ZTO stands for Zinc Tin Oxide
- ZTO stands for Zentrum fur Technische Orthopadie (German: Center for Technical Orthopedics)
- ZTO stands for Zaklad Techniki Odpylania (Polish: Department of Dust Removal Technology)
- ZTO stands for Zambezi Times Online (news website; Zambia)
- ZTO stands for Zero Time Outage
- ZTO stands for Zone Transportation Office
- ZTO stands for Zoom Theory Optimal (poker)
- ZTO stands for Zone Transportation Officer
Abbreviations And Their Meaning