| Church & Society, The United Methodist Church | DC |
| Chewonki Foundation | ME |
| Chattooga Conservancy | GA |
| Cetacean Society International | CT |
| Center for Wildlife Information | MT |
| Center for Biological Diversity | DC |
| Cascadia Wildlands | OR |
| Cascadia Forest Defenders | OR |
| Canada Goose Project | NY |
| Cambridge Woodfire Pottery | WI |
| California Wilderness Coalition | CA |
| California Trout | CA |
| California Native Plant Society | CA |
| Butterfly Farms.org | CA |
| Butte Environmental Council | CA |
| Buffalo Outdoor Center | AR |
| Buffalo Field Campaign | MT |
| Bucks County Audubon Society | PA |
| Buckeye Environmental Network | OH |
| Bowling Green-Warren County Humane Society | KY |
| Boulder Rights of Nature | CO |
| Born Free | MD |
| Black Bear Conservation Coalition | LA |
| BirdNote | WA |
| Berkshire Environmental Action Team (BEAT) | MA |
