TCS may stand for:
- Tactical cryptologic system
- Taking Children Seriously (tcs.ac)
- Tata Consultancy Services (tcs.com)
- Taxpayers for Common Sense
- Tech Central Station
- Television Corporation of Singapore
- Temperature compensation sensor
- The Coastal Society
- The Crustacean Society
- Theoretical computer science
- Thermal control subsystem
- Tongass Conservation Society
- Toronto Choral Society
- Total cross section
- Total customer satisfaction
- Touring Club Suisse (tcs.ch)
- Train Collectors Society
- Treasury Communications System (USA)
- Troop carrier squadron
- Trusted computer system
- Tucson Computer Society
- Tulsa Computer Society (tcs.org)
- Twickenham Choral Society
- Tactical control system
- Telescope control system
- Test control system
- Thermal control system
- Traction control system
- Train control system
- Trajectory control system
- Transaction control system
- Turbine control system