| RIAS | Rabo International Advisory Services 
| Others |
| RIAS | Radio in the America Sector
| Others |
| RIAS | Radio In the American Se
| Others |
| RIAS | Radio In the American Sector
| Others |
| RIAS | Recording Industry Association of Singapore
| Others |
| RIAS | Recording Industry Association Singapore
| Others |
| RIAS | Regulatory Impact Analysis Statement
| Others |
| RIAS | Remote infrared audible signage
| Others |
| RIAS | Remote Installation Assistance Service
| Others |
| RIAS | Research Institute for Advanced Studies
| Others |
| RIAS | Research Institute for Autonomous Systems
| Others |
| RIAS | Review of International American Studies
| Others |
| RIAS | Reynolds Intellectual Assessment Scales
| Others |
| RIAS | Rochester International Auto Show
| Others |
| RIAS | Roter interaction analysis system
| Others |
| RIAS | Rotor Interaction Analysis System
| Others |
| RIAS | Royal Incorporation of Architects in Scotland
| Others |
| RIAS | Rundfunk Im Amerikanischen Sektor
| Others |
| RIAS | Rutgers Integrated Administrative System
| Others |