Organizations
Largest first
By revenue on the last return. Organizations that file Form 990-N report no figures and come last.
| Organization | Return | Revenue |
|---|---|---|
| Climate United FundBethesda | Form 990 | $48,862,682FY2025 |
| National Marine Sanctuary FoundationSilver Spring | Form 990 | $35,981,845FY2024 |
| Chesapeake Bay Foundation IncAnnapolis | Form 990 | $35,411,298FY2025 |
| Montgomery County Green Bank CorpRockville | Form 990 | $25,520,849FY2025 |
| Alliance for the Chesapeake Bay IncAnnapolis | Form 990 | $16,008,340FY2024 |
| Chesapeake Conservancy IncAnnapolis | Form 990 | $14,019,453FY2025 |
| Oceantic Network IncBaltimore | Form 990 | $11,861,147FY2024 |
| Shorerivers IncEaston | Form 990 | $11,318,514FY2025 |
| Trees for the Future IncSilver Spring | Form 990 | $9,902,681FY2025 |
| Environmental Policy Innovation CenterCollege Park | Form 990 | $7,878,605FY2025 |
| Southern Maryland Resource Conservation & Development BoardLeonardtown | Form 990 | $7,353,752FY2025 |
| Wild Earth Allies IncChevy Chase | Form 990 | $6,966,259FY2025 |
| Nature Forward IncChevy Chase | Form 990 | $5,949,818FY2025 |
| Western Maryland Resource Conservation and DevelopmentHagerstown | Form 990 | $5,931,718FY2025 |
| Baltimore Tree Trust IncBaltimore | Form 990 | $5,832,783FY2024 |
| Land Preservation Trust IncCockeysville | Form 990 | $5,508,404FY2024 |
| Solid Waste Association of North America IncSilver Spring | Form 990 | $5,379,937FY2025 |
| National Park Trust IncRockville | Form 990 | $4,747,069FY2025 |
| Maryland Coastal Bays Foundation IncBerlin | Form 990 | $4,487,060FY2025 |
| Chesapeake Climate Action NetworkTakoma Park | Form 990 | $4,012,442FY2025 |
| Izaak Walton League of America IncGaithersburg | Form 990 | $3,965,623FY2025 |
| Irvine Natural Science Center IncOwings Mills | Form 990 | $3,825,601FY2025 |
| American Lumber Standard Committee IncorporatedFrederick | Form 990 | $3,815,109FY2025 |
| Center for Watershed ProtectionFulton | Form 990 | $3,779,842FY2024 |
| Moonshot Missions IncBethesda | Form 990 | $3,760,860FY2025 |
| Rachel Carson Council IncBethesda | Form 990 | $3,621,641FY2025 |
| Blue Water BaltimoreBaltimore | Form 990 | $3,610,893FY2025 |
| Arundel Rivers Federation IncEdgewater | Form 990 | $3,510,892FY2025 |
| Foundations of Success IncBethesda | Form 990 | $3,095,063FY2024 |
| Rock Creek Conservancy IncBethesda | Form 990 | $2,853,507FY2025 |
| Anacostia Watershed Society IncBladensburg | Form 990 | $2,620,455FY2024 |
| National Council on Radiation Protection and MeasurementsBethesda | Form 990 | $2,512,970FY2024 |
| Potomac Conservancy IncBethesda | Form 990 | $2,484,325FY2025 |
| Howard County Conservancy IncWoodstock | Form 990 | $2,398,216FY2024 |
| Mid Atlantic Regional Air Management Assocation IncTowson | Form 990 | $2,263,191FY2025 |
| Public Employees for Environmental Responsibility IncSilver Spring | Form 990 | $2,229,404FY2025 |
| Chesapeake Research Consortium IncEdgewater | Form 990 | $2,205,150FY2025 |
| Maryland Forestry Boards Foundation IncAnnapolis | Form 990 | $2,122,038FY2025 |
| Alice Ferguson Foundation IncAccokeek | Form 990 | $2,060,334FY2025 |
| Friends of Patterson Park IncBaltimore | Form 990 | $2,051,787FY2024 |
| Upstream Alliance IncAnnapolis | Form 990 | $2,026,911FY2025 |
| Voices for a Sustainable Future IncTakoma Park | Form 990 | $1,965,090FY2024 |
| C&O Canal Trust IncWilliamsport | Form 990 | $1,909,178FY2025 |
| Anne Arundel County Watershed Stewards Academy IncMillersville | Form 990 | $1,880,789FY2025 |
| Howard Ecoworks IncColumbia | Form 990 | $1,845,646FY2025 |
| Eastern Shore Land Conservancy IncEaston | Form 990 | $1,829,948FY2025 |
| Environmental Concern IncSaint Michaels | Form 990 | $1,792,207FY2024 |
| Majority ActionSilver Spring | Form 990 | $1,511,754FY2024 |
| Maryland League of Conservation Voters Education FundAnnapolis | Form 990 | $1,496,243FY2024 |
| Chesapeake Legal Alliance IncAnnapolis | Form 990 | $1,494,878FY2025 |
1 to 50 of 517