| G1R | Group One Racing 
| Others |
| G1S | Good One Side
| Others |
| G2 | Exceptional intelligence or information
| Others |
| G2 | Intelligence Staff at Corps and Division
| Others |
| G2 SEC | Intelligence Section
| Others |
| G20 | Group of 20
| Others |
| G2A | Go2Arena
| Others |
| G2B | Government to Business
| Others |
| G2B | Grid to Battery
| Others |
| G2C | Gen Two Club
| Others |
| G2C | Government to Citizen
| Others |
| G2C | Government to Customer
| Others |
| G2C | Government-to-Citizen
| Others |
| G2CU | Glad To See You
| Others |
| G2D | Gateway to Desktop
| Others |
| G2E | Global Gaming Expo
| Others |
| G2E | Government to Enterprises
| Others |
| G2G | Gateway to Gateway
| Others |
| G2G | Global to Global
| Others |
| G2G | Good to God
| Others |
| G2G | Government-To-Government
| Business, Government |
| G2G | Gray to Gray
| Others |
| G2G | Green to Green
| Others |
| G2K | Good to know
| Others |
| G2L | Gallons to Liters
| Others |
| G2L | Global to Local
| Others |
| G2M | Go To Market
| Others |
| G2N | Gen Two Network
| Others |
| G2NM | Gen Two Network Malaysia
| Others |
| G2OC | Gen Two Owners Club
| Others |
| G2R | Got to Run
| Others |
| G2S | General to Specific
| Others |
| G2SS | Guide to Safe Scouting
| Others |
| G2SYS | G2 Systems Corporation
| Others |
| G2V | Grid to Vehicle
| Others |
| G3 | Bitmap graphics (Group 3 FAX file)
| Others |
| G3 | Operations, Plans and Training Staff at Corps and Division
| Others |
| G3 OPNS | Current Operations Element of the G3 Section
| Others |
| G3 PLANS | Plans Element of the G3 Section
| Others |
| G30 | Group of 30
| Others |
| G36C | Gewehr 36 Carbine (Rifle 36 Carbine)
| Others |
| G36K | Gewehr 36 Kurz (Rifle 36 Short)
| Others |
| G3A | Air Operations Element of the G3 Section
| Others |
| G3C | Georgia Cyber Crime Center
| Others |
| G3G | Global 3g
| Others |
| G3K | Gumball 3000
| Others |
| G3KR | Gumball 3000 Rally
| Others |
| G3L | Gnu Linux et Logiciels Libres
| Others |
| G3P | Glyceraldehyde-3-Phosphate
| Others |
| G4 | Logistics Staff at Corps and Division
| Others |