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. Lakeville Community Conservancy Inc

    EIN 474221197 · Headquarters: lakeville, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  2. Land Conservancy of Ridgefield Inc

    EIN 066087261 · Headquarters: Ridgefield, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  3. Land Heritage Coalition of Glastonbury Inc

    EIN 061156347 · Headquarters: South Glastonbury, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  4. Land Trust of Darien Inc

    EIN 066068554 · Headquarters: DARIEN, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  5. Land Trust of West Haven Inc

    EIN 061325505 · Headquarters: WEST HAVEN, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  6. Lantern Hill Valley Association Inc

    EIN 237260147 · Headquarters: LEDYARD, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  7. Laurel Garden Club of Beacon Falls

    EIN 060945666 · Headquarters: Beacon Falls, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  8. Lesleys Recycling Corp

    EIN 881571157 · Headquarters: Stamford, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  9. Lime Rock Committee Inc

    EIN 204211998 · Headquarters: LAKEVILLE, CT, US · Environment · Latest available filing year: 2009 · Primary form: IRS Form 990-N

  10. Litchfield Green Conservancy Inc

    EIN 880570912 · Headquarters: Waterbury, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  11. Litchfield Hills Audubon Society Inc

    EIN 066036180 · Headquarters: LITCHFIELD, CT, USA · Environment · Latest available filing year: 2022 · Primary form: IRS Form 990

  12. Litchfield Hills Conservancy Inc

    EIN 800313962 · Headquarters: Winsted, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  13. Litchfield Land Trust Inc

    EIN 237002462 · Headquarters: LITCHFIELD, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  14. Little Pond Improvement Association

    EIN 332200975 · Headquarters: Thompson, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  15. Live Green Connecticut Inc

    EIN 271528832 · Headquarters: FAIRFIELD, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  16. Long Pond Common Land Trust Co

    EIN 462795986 · Headquarters: LEDYARD, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-PF

  17. Lower Connecticut River Land Trust Inc

    EIN 061166096 · Headquarters: Essex, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  18. Lyme Land Conservation Trust Inc

    EIN 066085183 · Headquarters: LYME, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  19. Mad Gardeners Inc

    EIN 030474394 · Headquarters: SHERMAN, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  20. Madison Land Conservation Trust

    EIN 066070866 · Headquarters: MADISON, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  21. Manresa Association

    EIN 474381888 · Headquarters: Norwalk, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  22. Mansfield Environmental Trust Inc

    EIN 814781698 · Headquarters: Storrs Mansfield, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  23. March Against Revenge Porn Inc

    EIN 853584051 · Headquarters: Wolcott, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  24. Mattabesset River Watershed Association

    EIN 061483655 · Headquarters: Kensington, CT, US · Environment · Latest available filing year: 2009 · Primary form: IRS Form 990-N

  25. Mccourt Memorial Garden in Memory of Sept 11Th Victims of Se Ct Inc

    EIN 611441335 · Headquarters: Mystic, CT, US · Environment · Latest available filing year: 2019 · Primary form: IRS Form 990-N

  26. Mclean Game Refuge Inc

    EIN 261960261 · Headquarters: SIMSBURY, CT, USA · Environment · Latest available filing year: 2023 · Primary form: IRS Form 990

  27. Mercury Masters

    EIN 470847491 · Headquarters: Norwalk, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  28. Merritt Parkway Conservancy

    EIN 061627645 · Headquarters: STAMFORD, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  29. Meshomasic Hiking Club Inc

    EIN 204505598 · Headquarters: Cobalt, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  30. Mianus River Watershed Council Inc

    EIN 223177286 · Headquarters: Greenwich, CT, US · Environment · Latest available filing year: 2013 · Primary form: IRS Form 990-N

  31. Middlebury Land Trust Inc

    EIN 237050688 · Headquarters: MIDDLEBURY, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  32. Middlesex Land Trust

    EIN 222812942 · Headquarters: MIDDLETOWN, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  33. Milford Environmental Protection Initiative Inc

    EIN 861101761 · Headquarters: Milford, CT, US · Environment · Latest available filing year: 2015 · Primary form: IRS Form 990-N

  34. Milford Trees Incorporated

    EIN 311751497 · Headquarters: Milford, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  35. Mill River Wetland Committee Inc

    EIN 060859820 · Headquarters: FAIRFIELD, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  36. Monroe Land Trust and Tree Conservancy Inc

    EIN 451674065 · Headquarters: Monroe, CT, US · Environment · Latest available filing year: 2022 · Primary form: IRS Form 990-N

  37. Moosup Pond Lakefront Association

    EIN 262304222 · Headquarters: Moosup, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  38. Morris Land Trust Inc

    EIN 352286224 · Headquarters: BANTAM, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  39. Morse Wilson Family Foundation

    EIN 873894365 · Headquarters: TRUMBULL, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-PF

  40. Mothers Natures Garden of Killingly Ct

    EIN 474540224 · Headquarters: DANIELSON, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  41. Mountain Laurel Trail Assoc Inc

    EIN 061323588 · Headquarters: KENT, CT, US · Environment · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  42. Mudge Pond Association Inc

    EIN 332573442 · Headquarters: Sharon, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  43. Naromi Land Trust Inc C/o Northwest Connecticut Land Cons

    EIN 060848037 · Headquarters: KENT, CT, USA · Environment · Latest available filing year: 2019 · Primary form: IRS Form 990

  44. National Senior Conservation Corps Inc

    EIN 262128111 · Headquarters: HAMDEN, CT, USA · Environment · Latest available filing year: 2017 · Primary form: IRS Form 990-EZ

  45. Natural Dividends Inc

    EIN 851218753 · Headquarters: West Hartford, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  46. Nature Initiative Inc

    EIN 550903854 · Headquarters: ROWAYTON, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  47. Naubesatuck Watershed Council Inc

    EIN 061569352 · Headquarters: Willimantic, CT, US · Environment · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  48. Naugatuck Land Trust Corp

    EIN 061532886 · Headquarters: Naugatuck, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  49. Naugatuck River Revival Group

    EIN 352334025 · Headquarters: Naugatuck, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  50. Naugatuck River Watershed Association Inc

    EIN 061417459 · Headquarters: middlebury, CT, US · Environment · Latest available filing year: 2017 · Primary form: IRS Form 990-N

  51. Naugatuck Valley Audubon Society Inc

    EIN 562319342 · Headquarters: Derby, CT, US · Environment · Latest available filing year: 2014 · Primary form: IRS Form 990-N

  52. New Canaan Beautification League Inc

    EIN 066082036 · Headquarters: New Canaan, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  53. New Canaan Environmental Group Inc

    EIN 061522243 · Headquarters: Darien, CT, US · Environment · Latest available filing year: 2010 · Primary form: IRS Form 990-N

  54. New Canaan Garden Club Inc

    EIN 066036288 · Headquarters: NEW CANAAN, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  55. New Canaan Nature Center

    EIN 060775150 · Headquarters: New Canaan, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  56. New England Historic Cemetery Restoration Project Inc

    EIN 843930241 · Headquarters: DANIELSON, CT, US · Environment · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  57. New Fairfield Land Trust Inc

    EIN 061490502 · Headquarters: NEW FAIRFIELD, CT, USA · Environment · Latest available filing year: 2015 · Primary form: IRS Form 990

  58. New Haven Bonsai Society Inc

    EIN 061600806 · Headquarters: New Haven, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  59. New Haven Green Fund Inc

    EIN 263730695 · Headquarters: NEW HAVEN, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  60. New London Trees Inc

    EIN 850848311 · Headquarters: New London, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  61. New Pond Farm Education Center Inc

    EIN 061110833 · Headquarters: WEST REDDING, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  62. New Roxbury Land Trust Inc

    EIN 061586014 · Headquarters: East Woodstock, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  63. Newtown Earth Day Inc

    EIN 262427415 · Headquarters: Newtown, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-PF

  64. Newtown Forest Association Inc

    EIN 066079549 · Headquarters: Newtown, CT, USA · Environment · Latest available filing year: 2023 · Primary form: IRS Form 990

  65. Newtown Residential Preservation Society

    EIN 412063902 · Headquarters: Newtown, CT, US · Environment · Latest available filing year: 2007 · Primary form: IRS Form 990-N

  66. Niantic Watershed Committee Inc

    EIN 352495465 · Headquarters: East Lyme, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  67. Noahs Dove Inc

    EIN 842050078 · Headquarters: New Haven, CT, US · Environment · Latest available filing year: 2019 · Primary form: IRS Form 990-N

  68. Nod Road Preservation Inc

    EIN 825486306 · Headquarters: AVON, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  69. Norfolk Land Trust Inc

    EIN 061072464 · Headquarters: NORFOLK, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  70. North American Marine Environment Protection Association Inc

    EIN 371552329 · Headquarters: WESTON, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  71. North Branford Conservation Trust Inc

    EIN 066105066 · Headquarters: North Branford, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  72. North Central Conservation District Inc

    EIN 060845763 · Headquarters: VERNON, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  73. North Greenwich Association Inc

    EIN 061178657 · Headquarters: Greenwich, CT, US · Environment · Latest available filing year: 2012 · Primary form: IRS Form 990-N

  74. North Woods Land Conservancy Inc

    EIN 205297138 · Headquarters: EAST HARTLAND, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  75. Northeast Environmental Balancing Bureau

    EIN 066205550 · Headquarters: SOUTHINGTON, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  76. Northern Connecticut Land Trust Inc

    EIN 222935986 · Headquarters: Somers, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  77. Northington Meadow

    EIN 342051088 · Headquarters: Avon, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-PF

  78. Northwest Connecticut Land Conservancy Inc

    EIN 066082034 · Headquarters: KENT, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  79. Northwest Connecticut Sportsmans Land Trust Inc

    EIN 844439650 · Headquarters: HARWINTON, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  80. Northwest Conservation District Inc

    EIN 060869263 · Headquarters: Torrington, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  81. Northwest Corner Preservation Inc

    EIN 811735909 · Headquarters: LAKEVILLE, CT, USA · Environment · Latest available filing year: 2020 · Primary form: IRS Form 990-EZ

  82. Norwalk Harbor Keeper

    EIN 822305143 · Headquarters: NORWALK, CT, USA · Environment · Latest available filing year: 2021 · Primary form: IRS Form 990-PF

  83. Norwalk Land Trust Inc

    EIN 237309817 · Headquarters: NORWALK, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  84. Norwalk River Watershed Association Inc

    EIN 061483326 · Headquarters: Wilton, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  85. Norwalk Tree Alliance Inc

    EIN 651170687 · Headquarters: NORWALK, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  86. Nu Krew LLC

    EIN 851046046 · Headquarters: Litchfield, CT, USA · Environment · Latest available filing year: 2023 · Primary form: IRS Form 990-PF

  87. Nutmeg Land Trust Inc

    EIN 061594523 · Headquarters: Torrington, CT, US · Environment · Latest available filing year: 2015 · Primary form: IRS Form 990-N

  88. Nutmeg State Orchid Society

    EIN 830511469 · Headquarters: Farmington, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  89. Ocean Connect Inc

    EIN 920453960 · Headquarters: Wilton, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  90. Ocean Exploration Trust Inc

    EIN 830488383 · Headquarters: NEW LONDON, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  91. Old Lyme Land Trust Inc

    EIN 066085184 · Headquarters: OLD LYME, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  92. Old Saybrook Coastal Resilience Coalition Inc

    EIN 922947323 · Headquarters: Old Saybrook, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  93. Old Saybrook Land Trust Inc

    EIN 061487669 · Headquarters: OLD SAYBROOK, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  94. On the Salt Co

    EIN 992665566 · Headquarters: OLD SAYBROOK, CT, US · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  95. Oseas Conservation Foundation Inc

    EIN 465546130 · Headquarters: RIDGEFIELD, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990

  96. Outdoor Stewards of Conservation Foundation Inc

    EIN 863710407 · Headquarters: MIDDLEBURY, CT, USA · Environment · Latest available filing year: 2024 · Primary form: IRS Form 990

  97. Oxford Main Street Project Corporation

    EIN 830807750 · Headquarters: OXFORD, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  98. Pachaug Pond Weed Control Association Inc

    EIN 822067695 · Headquarters: JEWETT CITY, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  99. Park City Compost Initiative Inc

    EIN 881149577 · Headquarters: Bridgeport, CT, USA · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-EZ

  100. Park Watershed Inc

    EIN 800913419 · Headquarters: Hartford, CT, US · Environment · Latest available filing year: 2025 · Primary form: IRS Form 990-N

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