| Abbreviation | Definition |
|---|---|
| RILS | Residences for Independent Living Society |
| RINA | Royal Institution of Naval Architects |
| RIPHH | Royal Institute of Public Health & Hygiene and Society of Public Health |
| RIRS | Rhode Island Radiology Society |
| RIRS | Rhode Island Rose Society |
| RISPE | Rhode Island Society of Professional Engineers |
| RJA&HS | Royal Jersey Agricultural & Horticultural Society |
| RJOS | Ruth Jackson Orthopaedic Society |
| RJOS | Ruth Jackson Orthopedic Society |
| RKS | Randall Knife Society |
| RLAS | Royal Lancashire Agricultural Society |
| RLASS | Rochester Ladies Anti Slavery Society |
| RLSS | Royal Life Saving Society |
| RMAG | Rocky Mountain Association of Geologists |
| RMAS | Rhein Main Aviation Society |
| RMBS | Rocky Mountain Bonanza Society |
| RMDS | Rocky Mountain Dressage Society |
| RMFS | Richmond Music Festival Society |
| RMJHS | Rocky Mountain Jewish Historical Society (Denver, CO) |
| RMKS | Rocky Mountain Ki Society |