| IMSI | Idaho Maximum Security Institution 
| Others |
| IMSI | Infrastructure Management and Security Information
| Others |
| IMSI | Integrated Management Systems Inc
| Others |
| IMSI | Integrated Modular Systems Inc
| Others |
| IMSI | Interface Marketing Supplier Integration
| Others |
| IMSI | International Maple Syrup Institute
| Others |
| IMSI | International Microcomputer Software Inc.
| Others |
| IMSI | International Microcomputer Software, Incorporated
| Others |
| IMSI | International Mobil Subscription Identity
| Others |
| IMSI | International Mobile Station Equipment Identity
| Others |
| IMSI | International Mobile Subscriber Identity
| Others |
| IMSI | International Mobile System Identifier
| Others |