| Braddock Run Watershed AssociationLa Vale | Form 990-N | No figure |
| H2ECO Foundation IncTowson | Form 990-N | No figure |
| Bear Branch Sanctuary IncBryans Road | Form 990-N | No figure |
| Environmental Justice Oral History ProjectUpper Marlboro | Form 990-N | No figure |
| SLM Native Bloom HavenLaurel | Form 990-N | No figure |
| O Lab IncTakoma Park | Form 990-N | No figure |
| Africa Environmental Watch & Services IncBowie | Form 990-N | No figure |
| Cedar Haven Civic Association on the Patuxent River IncBrandywine | Form 990-N | No figure |
| LIFE4SOFALA Foundation IncCambridge | Form 990-N | No figure |
| Pikesville Garden Club IncBaltimore | Form 990-N | No figure |
| Greater Washington Aquatic Plants AssociationLaurel | Form 990-N | No figure |
| Blue Moon Rising Center for Sustainable Education IncMcHenry | Form 990-N | No figure |
| Chesapeake Energy Conservation IncSaint Michaels | Form 990-N | No figure |
| Undescriptively Blessed Missionary IncBaltimore | Form 990-N | No figure |
| Union of Chinese American Professional Organizations IncRockville | Form 990-N | No figure |
| Friends of Cabin John Creek IncCabin John | Form 990-N | No figure |
| Climate First IncTakoma Park | Form 990-N | No figure |
| Watts Branch Watershed Alliance IncRockville | Form 990-N | No figure |
| Growth Action Network of Anne Arundel County IncArnold | Form 990-N | No figure |
| Friends of Chevy Chase CircleChevy Chase | Form 990-N | No figure |
| Sligo Creek Neighbors for a Sustainable CommunitySilver Spring | Form 990-N | No figure |
| Chesapeake Chapter of AwmaBaltimore | Form 990-N | No figure |
| Kent Island Beach Cleanups IncStevensville | Form 990-N | No figure |
| Elk and North East Rivers Watershed AssociationNorth East | Form 990-N | No figure |
| Center for Invasive Species Prevention IncBethesda | Form 990-N | No figure |
| Sugarloaf AllianceFrederick | Form 990-N | No figure |
| Urban Ecosystem Restorations IncBethesda | Form 990-N | No figure |
| Garden Club of Rock HallChestertown | Form 990-N | No figure |
| Change 4 Good IncorporatedFort Washington | Form 990-N | No figure |
| Friends of Ten Mile Creek and Little Seneca ReservoirClarksburg | Form 990-N | No figure |
| Friends of the Bohemia IncChesapeake City | Form 990-N | No figure |
| Cape Conservation CorpsAnnapolis | Form 990-N | No figure |
| Friends of Waterford Park IncFrederick | Form 990-N | No figure |
| Harford County Climate ActionBel Air | Form 990-N | No figure |
| 350 Montgomery County IncKensington | Form 990-N | No figure |
| Friends of Stevenson IncBaltimore | Form 990-N | No figure |
| Green Burial Association of Maryland IncCockeysville | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncBaltimore | Form 990 | $0FY2024 |
| The Federated Garden Clubs of Maryland IncCrownsville | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncBaltimore | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncColtons Point | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncColumbia | Form 990-N | No figure |
| Elk Creeks Preservation Society IncorporatedElk Mills | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncShady Side | Form 990-N | No figure |
| Maryland Orchid Society IncMount Airy | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncForest Hill | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncChester | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncMillersville | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncLa Plata | Form 990-N | No figure |
| Federated Garden Clubs Maryland IncChestertown | Form 990-N | No figure |