HST
- Harmonized sales tax
- Harry S. Truman
- Harvard–MIT Program in Health Sciences and Technology
- Hastings railway station, Melbourne
- Hawaii–Aleutian Standard Time
- Hegemonic stability theory
- Helicopter support team
- Helsinki City Transport
- Heritage Shunters Trust
- High Sierra Trail
- High Street (Glasgow) railway station
- High-speed telegraphy
- High-speed train
- High-speed transport
- History of science and technology
- Holden Street Theatres
- Homestead Air Reserve Base
- Hospital Santo Tomás
- Hubble Space Telescope
- Hunter S. Thompson
- InterCity 125
- USRobotics
- USS Harry S. Truman