| Organization | Address | State / Province | |
|---|---|---|---|
| Garden Club of America | NY Map It | NY | |
| Gasparilla Island Conservation | FL Map It | FL | |
| Gaviota Coast Conservancy | CA Map It | CA | |
| Georgia Highlands College | GA Map It | GA | |
| Georgia Native Plant Society | GA Map It | GA | |
| Glen Canyon Institute | UT Map It | UT | |
| Gotham Bat Conservancy | New York Map It | New York | |
| Government Accountability Project | DC Map It | DC | |
| Grand Canyon Trust | AZ Map It | AZ | |
| Grand Canyon Wildlands Council | AZ Map It | AZ | |
| Grand Canyon Wolf Recovery Project | AZ Map It | AZ | |
| Great Lakes Indian Fish and Widllfie Comission | WI Map It | WI | |
| Great Lakes United | NY Map It | NY | |
| Great Old Broads for Wilderness | CO Map It | CO | |
| Great Plains Restoration Council | TX Map It | TX | |
| Great South Bay Audubon Society | NY Map It | NY | |
| Greater Wyoming Valley Audubon Society | PA Map It | PA | |
| Greater Yellowstone Coalition | MT Map It | MT | |
| Green-Rock Audubon Society | WI Map It | WI | |
| Greenbelt Alliance | CA Map It | CA | |
| Greenpeace USA | DC Map It | DC | |
| Gulf Restoration Network | LA Map It | LA | |
| Gulf Specimen Marine Lab | FL Map It | FL | |
| HabitatYou | IA Map It | IA | |
| Harris Center for Conservation Education | NH Map It | NH | |
| Organization | Address | State / Province |
