| FIO | Factory Installable Option 
| Others |
| FIO | Factory Installation Option
| Others |
| FIO | Factory Installed Option
| Others |
| FIO | Fart It Off
| Others |
| FIO | Federal Insurance Office
| Others |
| FIO | Festival of International Opera
| Others |
| FIO | Fiber and Integrated Optics
| Others |
| FIO | Field Intelligence Observation
| Others |
| FIO | Field Intelligence Officer
| Others |
| FIO | Field Interrogation and Observation
| Others |
| FIO | Figure it Out
| Others |
| FIO | File I O
| Others |
| FIO | File Input Output
| Others |
| FIO | Financial Object
| Others |
| FIO | Fiolina is the only
| Others |
| FIO | Fire Inspection Officer
| Others |
| FIO | First Installed Option
| Others |
| FIO | First Institute of Oceanography
| Others |
| FIO | Flexible I O
| Others |
| FIO | flexible I/O
| Others |
| FIO | Florida InsideOut Magazine
| Others |
| FIO | Florida Institute of Oceanography
| Others |
| FIO | Flow Injection Operations
| Others |
| FIO | For Information Only
| Others |
| FIO | Force Integration Office
| Others |
| FIO | Forestry Industry Organization
| Others |
| FIO | Forms Input/ Output
| Others |
| FIO | Foundation for Interwallet Operability
| Others |
| FIO | Four In One
| Others |
| FIO | Fourier integral operator
| Others |
| FIO | Frame Input Output
| Others |
| FIO | Free In and Out
| Others |
| FIO | Free In Out
| Others |
| FIO | Frontiers in Optics
| Others |
| FIO | Funnel I O
| Others |
| FIO | Furnished and Installed by Others
| Others |
| FIO | Futaba Industrial of Ontario
| Others |
| FIO | Future Input Output
| Others |
| FIO | Future Input/ Output
| Others |
| FIO | Future Insurability Option
| Others |
| FIO | Graphics filter (Aldus PhotoStyler)
| Others |