| Acronym | Meaning |
| STS | Space Transportation System |
| STS | (USN Rating) Sonar Technician (Submarine) |
| STS | Salary Table Setup |
| STS | Sea Transport Staff (Australia) |
| STS | Sea-To-Sky (Highway Improvement Project; Canada) |
| STS | Seal Team Six |
| STS | Second Tier Supplier |
| STS | Secure Telephone System |
| STS | Security Technical Specialist (US State Department) |
| STS | Security Termination Statement |
| STS | Sensor to Service |
| STS | Sensor to Shooter |
| STS | Sentence To Serve |
| STS | Service des Tâches Spéciales (French: Service of Special Tasks) |
| STS | Serviciul de Telecomunicatii Speciale (Special Telephony Service; Romanian Secret Service) |
| STS | Servo-actuator Test Station |
| STS | Sewage Treatment Station (various locations) |
| STS | Shared Tenant Services |
| STS | Sheboygan Transit System (Sheboygan, WI) |
| STS | Ship to Ship |
| STS | Shuttle Test Station (US NASA) |
| STS | Simplified Tax System |
| STS | Single Trusted System |
| STS | SingStat Time Series (Singapore) |
| STS | Site Tracking System |
| STS | Small Traffic Station |
| STS | Software Test Station (oftware development, especially defense contacts) |
| STS | Special Tactical Services |
| STS | Special Tactics Squadron |
| STS | Special Transportation Service |
| STS | Specialized Treatment Service |
| STS | Specialty Training Standard |
| STS | Stabilized Tracking Set |
| STS | Standard Technical Specifications |
| STS | State Training School (various locations) |
| STS | State Training Services ( Australia) |
| STS | Station-To-Station Protocol |
| STS | Stockpile-to-Target Sequence |
| STS | Strategic Training Squadron |
| STS | Streets (US Postal service standard street suffix) |
| STS | Structural Transition Section (US NASA) |
| STS | Subcommittee on Telecommunications Security (NSTISSC) |
| STS | Submissions Tracking System |
| STS | Summer Training Schedule (US Navy) |
| STS | Surface To Surface |
| STS | System Technical Support |
| STS | System Test Set |
| STS | System Timing Step |
| STS | System to Standard |