Environment nonprofits in Connecticut

Environment nonprofits in Connecticut. Browse 566 public nonprofit profiles. Review organization identities, available filing years, and their complete CharitySense profiles.

Location refers to headquarters recorded in public sources, not an organization’s service area. Classification describes its reported category and does not assess its effectiveness.

Nonprofit profiles

  1. Friends of Hebron Parks Inc

    EIN 263441614 · Headquarters: Hebron, CT, US · Environment · Latest available filing year: 2014 · Primary form: IRS Form 990-N

  2. Friends of Lake Pocotopaug Inc

    EIN 141961680 · Headquarters: East Hampton, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  3. Friends of Lake Williams Inc

    EIN 061526560 · Headquarters: Hebron, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  4. Friends of Long Hill Estate Inc

    EIN 061463798 · Headquarters: Middletown, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  5. Friends of Machimoodus State Parks

    EIN 820889377 · Headquarters: Hadlyme, CT, US · Environment · Latest available filing year: 2022 · Primary form: IRS Form 990-N

  6. Friends of Manitook Lake

    EIN 262983500 · Headquarters: Granby, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  7. Friends of Mono Pond State Park Inc

    EIN 884062116 · Headquarters: COLUMBIA, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  8. Friends of North Cove

    EIN 833628780 · Headquarters: Old Saybrook, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  9. Friends of Old Quarry Nature Center Inc

    EIN 060960692 · Headquarters: New Milford, CT, US · Environment · Latest available filing year: 2009 · Primary form: IRS Form 990-N

  10. Friends of Outer Island Inc

    EIN 030475026 · Headquarters: Branford, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  11. Friends of Pachaug Forest Inc

    EIN 823981416 · Headquarters: griswold, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  12. Friends of Pameacha Pond-long Hill Brook Inc

    EIN 934279119 · Headquarters: Middletown, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  13. Friends of Pope Park Inc

    EIN 061663515 · Headquarters: HARTFORD, CT, US · Environment · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  14. Friends of Seaside State Park

    EIN 833127450 · Headquarters: New Canaan, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  15. Friends of Sellecks Woods Inc

    EIN 061225601 · Headquarters: DARIEN, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  16. Friends of Sherwood Island State Park

    EIN 061446244 · Headquarters: WESTPORT, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  17. Friends of the Cascapedia River Inc

    EIN 200780192 · Headquarters: Kent, CT, US · Environment · Latest available filing year: 2021 · Primary form: IRS Form 990-N

  18. Friends of the Farm River Estuary Inc

    EIN 753060920 · Headquarters: Branford, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  19. Friends of the Garden of Ideas Inc

    EIN 452207806 · Headquarters: ridgefield, CT, US · Environment · Latest available filing year: 2020 · Primary form: IRS Form 990-N

  20. Friends of the Lake

    EIN 200317010 · Headquarters: BRIDGEWATER, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  21. Friends of the Linear Trail Inc

    EIN 061530178 · Headquarters: Shelton, CT, US · Environment · Latest available filing year: 2022 · Primary form: IRS Form 990-N

  22. Friends of the Norwalk Islands Inc

    EIN 272892165 · Headquarters: Norwalk, CT, US · Environment · Latest available filing year: 2011 · Primary form: IRS Form 990-N

  23. Friends of the Norwalk River Valley Trail Inc

    EIN 451496672 · Headquarters: Georgetown, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  24. Friends of the Oswegatchie Hills Nature Preserve Inc

    EIN 061632142 · Headquarters: NIANTIC, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  25. Friends of the River

    EIN 300274197 · Headquarters: Durham, CT, US · Environment · Latest available filing year: 2007 · Primary form: IRS Form 990-N

  26. Friends of the Shetucket River Valley

    EIN 455519808 · Headquarters: Baltic, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  27. Friends of Topsmead State Forest Inc

    EIN 831308878 · Headquarters: Litchfield, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  28. Friends of West Side Pond Inc

    EIN 814017052 · Headquarters: Goshen, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  29. Friends of White Deer Rock Inc

    EIN 843835708 · Headquarters: MIDDLEBURY, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  30. Fromearth4earth Inc

    EIN 861945442 · Headquarters: MIDDLEBURY, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  31. Future Frogmen Inc

    EIN 843222259 · Headquarters: Milford, CT, US · Environment · Latest available filing year: 2019 · Primary form: IRS Form 990-N

  32. Gaia Nephal Inc

    EIN 463384159 · Headquarters: TRUMBULL, CT, US · Environment · Latest available filing year: 2018 · Primary form: IRS Form 990-N

  33. Garden Club of Madison

    EIN 066047068 · Headquarters: MADISON, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  34. Garden Club of Mamaroneck

    EIN 161691585 · Headquarters: WEST HAVEN, CT, US · Environment · Latest available filing year: 2012 · Primary form: IRS Form 990-N

  35. Gather New Haven Inc (Formely New Haven Land Trust Inc)

    EIN 061063389 · Headquarters: NEW HAVEN, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  36. George Campert Memorial Land Trust Inc

    EIN 061477497 · Headquarters: WOODSTOCK VALLEY, CT, USA · Environment · Latest available filing year: 2021 · Primary form: IRS Form 990-PF

  37. Georgetown Lions Club Inc

    EIN 454496775 · Headquarters: Redding, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  38. Glastonbury Partners in Planting Inc

    EIN 200186961 · Headquarters: SO GLASTONBURY, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  39. Goats for Good

    EIN 990622041 · Headquarters: GLASTONBURY, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  40. Going Coastal Inc

    EIN 161666507 · Headquarters: Stamford, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  41. Granby Land Trust Inc

    EIN 237243316 · Headquarters: Granby, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  42. Granby Wildflower Meadow

    EIN 872180879 · Headquarters: Granby, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  43. Grassroots Fund for the Environment Inc

    EIN 202986668 · Headquarters: Madison, CT, US · Environment · Latest available filing year: 2008 · Primary form: IRS Form 990-N

  44. Great Island Preservation Inc

    EIN 995082502 · Headquarters: DARIEN, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  45. Great River Land Trust Inc

    EIN 454128786 · Headquarters: EAST HARTFORD, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  46. Greater Bridgeport Community Enter

    EIN 205759623 · Headquarters: BRIDGEPORT, CT, USA · Environment · Latest available filing year: 2023 · Primary form: IRS Form 990

  47. Green Eco Warriors Incorporated

    EIN 800931267 · Headquarters: WINDSOR, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  48. Green Fingers Garden Club Inc

    EIN 061507939 · Headquarters: GREENWICH, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  49. Green Line Albania Inc

    EIN 812861238 · Headquarters: STORRS MANSFIELD, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  50. Greenway Land Trust of Southeastern Connecticut Inc

    EIN 474997057 · Headquarters: Groton, CT, US · Environment · Latest available filing year: 2018 · Primary form: IRS Form 990-N

  51. Greenwich Botanical Center Inc

    EIN 066068606 · Headquarters: COS COB, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  52. Greenwich Green & Clean Inc

    EIN 061187787 · Headquarters: GREENWICH, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  53. Greenwich Point Conservancy Inc

    EIN 300229904 · Headquarters: OLD GREENWICH, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  54. Groton Conservation Advocates Inc

    EIN 834308458 · Headquarters: Noank, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  55. Groton Open Space Association Inc

    EIN 061469419 · Headquarters: Groton, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  56. Guardian of the Galapagos Co

    EIN 841954044 · Headquarters: CHESHIRE, CT, USA · Environment · Latest available filing year: 2021 · Primary form: IRS Form 990-PF

  57. Guilford Community Garden Hub Inc

    EIN 465298239 · Headquarters: Guilford, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  58. Guilford Land Conservation Trust Inc

    EIN 060851698 · Headquarters: Guilford, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  59. Haddam Land Trust Inc

    EIN 066079139 · Headquarters: HADDAM, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  60. Hamden Homicide Memorial Botanical Garden of Healing

    EIN 922510293 · Headquarters: Hamden, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  61. Hardy Plant Society of New England Connecticut Chapter Inc

    EIN 061615495 · Headquarters: Franklin, CT, US · Environment · Latest available filing year: 2020 · Primary form: IRS Form 990-N

  62. Hartford Audubon Society Inc

    EIN 237118929 · Headquarters: West Hartford, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  63. Hartford Botanical Garden Planning Committee Inc

    EIN 061544913 · Headquarters: Hartford, CT, US · Environment · Latest available filing year: 2010 · Primary form: IRS Form 990-N

  64. Hartford Land Bank Inc

    EIN 823965276 · Headquarters: HARTFORD, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  65. Hartford Proud and Beautiful Foundation Inc

    EIN 223115001 · Headquarters: HARTFORD, CT, USA · Environment · Latest available filing year: 2015 · Primary form: IRS Form 990-PF

  66. Havens Harvest Inc

    EIN 850627932 · Headquarters: New Haven, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  67. Heritage Land Preservation Trust In

    EIN 510172264 · Headquarters: TORRINGTON, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  68. Highland Lake Watershed Association Inc

    EIN 061403617 · Headquarters: Winsted, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  69. Holcomb Farm Inc

    EIN 061384197 · Headquarters: West Granby, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  70. Home Garden Club of Wethersfield

    EIN 066080221 · Headquarters: Newington, CT, US · Environment · Latest available filing year: 2019 · Primary form: IRS Form 990-N

  71. Hop River Trail Alliance Inc

    EIN 931563263 · Headquarters: Bolton, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  72. Hortulus Inc

    EIN 066083165 · Headquarters: GREENWICH, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  73. Housatonic Audubon Society Inc

    EIN 510161436 · Headquarters: Sharon, CT, US · Environment · Latest available filing year: 2011 · Primary form: IRS Form 990-N

  74. Housatonic Environmental Action League Inc

    EIN 061618175 · Headquarters: Cornwall Bridge, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  75. Housatonic Valley Association Inc

    EIN 066049295 · Headquarters: CORNWALL BRIDGE, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  76. Hudson Bay Project Corporation

    EIN 061448157 · Headquarters: REDDING, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  77. Hummingbird Cay Foundation Inc

    EIN 237268623 · Headquarters: SOUTHPORT, CT, USA · Environment · Latest available filing year: 2020 · Primary form: IRS Form 990

  78. Huneebee Project Inc

    EIN 853837316 · Headquarters: NEW HAVEN, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  79. Hunt Hill Farm Trust

    EIN 141867440 · Headquarters: New Milford, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-PF

  80. Inclusive Prosperity Capital Inc

    EIN 830808658 · Headquarters: HARTFORD, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  81. Indian Lake Association of Connecticut and New York

    EIN 061113398 · Headquarters: SHARON, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  82. Inner Sound Habitats

    EIN 933937530 · Headquarters: West Hartford, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  83. Institute for Ocean Studies

    EIN 061515982 · Headquarters: NORTH HAVEN, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  84. Instituteofmanagementaccountantsinc

    EIN 237353194 · Headquarters: SHELTON, CT, US · Environment · Latest available filing year: 2016 · Primary form: IRS Form 990-N

  85. International Association of Sport and Play for Young Children

    EIN 822626621 · Headquarters: Hamden, CT, US · Environment · Latest available filing year: 2019 · Primary form: IRS Form 990-N

  86. Interreligious Eco-justice Network

    EIN 043737215 · Headquarters: Preston, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  87. Ives Trail and Greenway Regional Association

    EIN 461127798 · Headquarters: Danbury, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  88. Jeffersonian Enterprise for Flora and Fauna

    EIN 994146619 · Headquarters: Easton, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  89. Jill R Montgomery Memorial Land Trust Inc

    EIN 060946975 · Headquarters: Greenwich, CT, US · Environment · Latest available filing year: 2009 · Primary form: IRS Form 990-N

  90. Joshua's Tract Conservation and Historic Trust Inc

    EIN 066087579 · Headquarters: Mansfield Center, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  91. Keep America Beautiful Inc

    EIN 131761633 · Headquarters: STAMFORD, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  92. Keep Stamford Beautiful Inc

    EIN 061528027 · Headquarters: STAMFORD, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  93. Kent Garden Club

    EIN 473332630 · Headquarters: South Kent, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  94. Kent Land Trust Foundation Inc

    EIN 061599241 · Headquarters: KENT, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  95. Kent Land Trust Inc

    EIN 061257251 · Headquarters: KENT, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  96. King Cobra Conservancy Inc

    EIN 821173317 · Headquarters: BERLIN, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  97. Kings Mark Resource Conservation & Develop Proj Inc Agri Center

    EIN 060946873 · Headquarters: Bristol, CT, US · Environment · Latest available filing year: 2012 · Primary form: IRS Form 990-N

  98. Lake Beebe Watershed Association Ltd

    EIN 030372043 · Headquarters: WEST HARTFORD, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  99. Lake Quassapaug Association Inc

    EIN 462210426 · Headquarters: MIDDLEBURY, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  100. Lake Waramaug Task Force Inc

    EIN 061063687 · Headquarters: WARREN, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

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