| Friends of Crex IncGrantsburg | Form 990 | $407,596FY2024 |
| Victory Garden Initiative IncMilwaukee | Form 990 | $406,023FY2025 |
| Bus for Outdoor Access and TeachingMilwaukee | Form 990 | $374,506FY2025 |
| Green Lake Conservancy IncGreen Lake | Form 990 | $371,920FY2025 |
| Seno K RLT Conservancy IncBurlington | Form 990 | $369,363FY2024 |
| Friends of High Cliff State Park IncSherwood | Form 990 | $357,267FY2025 |
| International Energy Program Evaluation ConferenceMadison | Form 990 | $348,615FY2025 |
| Friends of San Damiano IncMonona | Form 990 | $337,155FY2024 |
| Sawyer County Snowmobile Alliance IncHayward | Form 990 | $335,096FY2025 |
| National Association of State Conservation AgenciesStevens Point | Form 990 | $326,288FY2024 |
| Wastecap Resource Solutions IncMilwaukee | Form 990 | $318,727FY2024 |
| Spider Chain of Lakes Improvement AssociationHayward | Form 990 | $318,322FY2025 |
| Friends of the Welty Environmental Center IncBeloit | Form 990 | $315,094FY2024 |
| Southeastern Wisconsin Invasive Species Consortium IncMilwaukee | Form 990 | $311,076FY2025 |
| Valley Stewardship Network IncViroqua | Form 990 | $303,104FY2025 |
| Wisconsin Woodland Owners Association IncorporatedStevens Point | Form 990 | $297,492FY2025 |
| Wisconsin Wildlife Federation IncPoynette | Form 990 | $286,173FY2024 |
| Waukesha County Land Conservancy IncBrookfield | Form 990 | $279,312FY2025 |
| Recycling Connections CorporationStevens Point | Form 990 | $275,476FY2025 |
| Friends of Schmeeckle Reserve IncStevens Point | Form 990 | $272,990FY2025 |
| Big Doctor Lake Assoc IncSiren | Form 990 | $267,558FY2025 |
| Shawano Lake Property Owners AssocShawano | Form 990 | $263,781FY2024 |
| Lake Owen Association IncCable | Form 990 | $259,290FY2024 |
| Friends of Kishwauketoe LtdWilliams Bay | Form 990 | $258,179FY2024 |
| Teens Take on Climate IncWaukesha | Form 990 | $253,820FY2024 |
| Freshair CollectiveMilwaukee | Form 990 | $249,706FY2025 |
| Deer Lake Conservancy IncorporatedSaint Croix Falls | Form 990 | $245,669FY2024 |
| Wisconsin Clean Cities-Southeast- Area IncMilwaukee | Form 990 | $240,945FY2025 |
| Milwaukee Audubon Society IncSouth Milwaukee | Form 990 | $236,492FY2025 |
| Riverwood Nature CenterStar Prairie | Form 990 | $223,054FY2024 |
| Federation of Environment Technologists IncWaukesha | Form 990 | $222,290FY2025 |
| Court Oreilles Lakes Association IncHayward | Form 990 | $218,866FY2025 |
| Garden Club of Greater MilwaukeeMukwonago | Form 990 | $217,858FY2025 |
| Des Plaines Wetlands Conservancy IncPleasant Prairie | Form 990 | $217,773FY2025 |
| Wisconsin Association of Lakes IncSun Prairie | Form 990 | $215,495FY2024 |
| Durwards Glen Olrg LtdBaraboo | Form 990 | $214,273FY2025 |
| Lake Geneva Garden Club Foundation IncLake Geneva | Form 990 | $208,977FY2025 |
| Waterways Association of Menominee and Shawano Counties IncShawano | Form 990 | $204,619FY2024 |
| Baird Creek Preservation Foundation IncGreen Bay | Form 990 | $192,608FY2025 |
| Further Along IncViroqua | Form 990 | $190,185FY2025 |
| Shadows on the Wolf IncShiocton | Form 990 | $189,830FY2025 |
| Friends of Lake Henry IncBlair | Form 990 | $187,752FY2024 |
| Wisconsin Local Government Climate Coalition IncMadison | Form 990-EZ | $186,815FY2024 |
| Van Der Brohe Arboretum IncTwo Rivers | Form 990 | $183,860FY2024 |
| Friends of Lac Lawrann Conservancy IncWest Bend | Form 990-EZ | $176,864FY2025 |
| Crawford Stewardship Project LtdGays Mills | Form 990-EZ | $175,189FY2025 |
| Associated Recyclers of Wisconsin IncStevens Point | Form 990-EZ | $173,260FY2025 |
| Friends of Fred Smith IncPhillips | Form 990 | $171,556FY2025 |
| Round Lake Property Owners Assn IncHayward | Form 990-EZ | $165,033FY2024 |
| Upper Sugar River Watershed AssociationMount Horeb | Form 990-EZ | $164,562FY2024 |