| Black Swamp Creek Land TRBrandywine | Form 990-N | No figure |
| Envirosynergy IncorporatedBethesda | Form 990-N | No figure |
| Belvedere Community Association IncArnold | Form 990-N | No figure |
| Chesapeake Bay Herb Society IncEaston | Form 990-N | No figure |
| Neighbors of the Northwest Branch IncSilver Spring | Form 990-N | No figure |
| Ukrainian American Environmental AssociationTakoma Park | Form 990-N | No figure |
| Broadwater Creek Coalition IncChurchton | Form 990-N | No figure |
| Piedmont Environmental and Education Foundation IncBarnesville | Form 990-N | No figure |
| Proactive Science IncLusby | Form 990-N | No figure |
| Savefairhill IncElkton | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncHagerstown | Form 990-N | No figure |
| Daughters of Union Veterans of the Civil War 1861-1865Jessup | Form 990-N | No figure |
| Daughters of Union Veterans of the Civil War 1861-1865Jessup | Form 990-N | No figure |
| Tanta Cove Garden ClubFort Washington | Form 990-N | No figure |
| Federated Garden Clubs of Maryland IncSaint Michaels | Form 990-N | No figure |
| Advocates for Herring BayTracys Landing | Form 990-N | No figure |
| Dorchester Citizens for Plannedgrowth IncCambridge | Form 990-N | No figure |
| Native Grassland Conservancy IncUpper Marlboro | Form 990-N | No figure |
| Friends of Still Creek IncGreenbelt | Form 990-N | No figure |
| Greennonprofits Org IncColumbia | Form 990-N | No figure |
| Hyattsville Horticultural SocietyHyattsville | Form 990-N | No figure |
| Help Our Marine Environment IncChevy Chase | Form 990-N | No figure |
| Antietam-Conococheague Watershed Alliance IncHagerstown | Form 990-N | No figure |
| Mattawoman Watershed SocietyAccokeek | Form 990-N | No figure |
| Maryland Stream Restoration AssociationGambrills | Form 990-N | No figure |
| Community Research IncCollege Park | Form 990-N | No figure |
| Catoctin Forest Alliance IncThurmont | Form 990-N | No figure |
| Spriggs Farm Preservation Foundation IncArnold | Form 990-N | No figure |
| Poolesville GreenPoolesville | Form 990-N | No figure |
| Takoma Park Computer Recovery Center IncCapitol Heights | Form 990-N | No figure |
| Seneca Creek Watershed Partners IncGaithersburg | Form 990-N | No figure |
| Friends of Seneca Creek Patuxent River State Parks IncNorth Potomac | Form 990-N | No figure |
| Homeland Community FoundationBaltimore | Form 990-N | No figure |
| Sugarloaf Countryside Conservancy IncClarksburg | Form 990-N | No figure |
| Nanjemoy Vision IncNanjemoy | Form 990-N | No figure |
| Malachi Water Winds Woods Foundation IncReisterstown | Form 990-N | No figure |
| Friends of Greenbury Point IncAnnapolis | Form 990-N | No figure |
| Serenity Ridge Nature Preserve and Arboretum IncWindsor Mill | Form 990-N | No figure |
| Coral Triangle Conservation FundTakoma Park | Form 990-EZ | $0FY2025 |
| African Islands Business CouncilLaurel | Form 990-N | No figure |
| Project Green SweepPotomac | Form 990-N | No figure |
| Anns Backyard Forest LtdBethesda | Form 990-N | No figure |
| Global Water Promise CorpBaltimore | Form 990-N | No figure |
| Community Design LabGermantown | Form 990-N | No figure |
| Friends of Wormans Mill ParkFrederick | Form 990-N | No figure |
| Winters Harvest Homestead IncOakland | Form 990-N | No figure |
| Green Infrastructure Leadership ExchangeParkville | Form 990-N | No figure |
| Brooklandville StationLutherville | Form 990-N | No figure |
| Bucktail Rod & Gun Club of Arnold IncArnold | Form 990-N | No figure |
| Brook South Fultons Camp Creek Conservation Club IncTowson | Form 990-N | No figure |