| Abbreviation | Definition |
|---|---|
| IOCS | Inside-Out Cleaning Services |
| IOCS | International Offshore Company Services, Inc. |
| IODA | Independent On-line Distribution Alliance |
| IOEC | Indian Ocean Export Company |
| IOF | Independent Order of Foresters [Insurance Firm] |
| IOFSA | Indian Ordnance Factories officers Association |
| IOI | Independent Opportunities Inc |
| IOI | Industrial Opportunities Inc |
| IOL | Indian Oil Coporation Ltd |
| IOL | Israel Online |
| IOLI | International Organization of Lace Inc |
| IOOC | Iranian Offshore Oil Company |
| IOP | Industrial Opportunity Partners |
| IOP | Internet Optimized Publicity |
| IOP | Isle Of Palms |
| IOR | Industrie Optic Romania |
| IOR | Industries Optical de Romania |
| IOS | Ikea Of Sweden |
| IOSC | Iranian Oilfield Services Company |
| IOSL | Indian Oil Skytanking Ltd |