Unknown & Unclassified nonprofits in Connecticut

Unknown & Unclassified nonprofits in Connecticut. Browse 7,402 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. Sigma Gamma Rho Sorority Inc

    EIN 311445516 · Headquarters: Hartford, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  2. Sigma Gamma Rho Sorority Inc

    EIN 550904055 · Headquarters: NEW HAVEN, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  3. Sigma Nu Fraternity

    EIN 900824346 · Headquarters: West Hartford, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  4. Sigma Phi Alpha Dental Hygiene Honor Society

    EIN 066087862 · Headquarters: Bridgeport, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  5. Sigma Phi Alpha Dental Hygiene Honor Society

    EIN 911895155 · Headquarters: Farmington, CT, US · Unknown & Unclassified · Latest available filing year: 2022 · Primary form: IRS Form 990-N

  6. Sigma Phi Alpha Dental Hygiene Honor Society

    EIN 911940781 · Headquarters: West Haven, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  7. Sigma Sigma Sigma Inc

    EIN 474190476 · Headquarters: Naugatuck, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  8. Sigma Theta Tau Inc

    EIN 311242958 · Headquarters: Danbury, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  9. Sigma Theta Tau Inc

    EIN 311361605 · Headquarters: Fairfield, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  10. Sigma Theta Tau International Inc

    EIN 066070315 · Headquarters: STORRS, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  11. Sigma Theta Tau International Inc

    EIN 311309952 · Headquarters: Fairfield, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  12. Sigma Theta Tau International Inc

    EIN 621092017 · Headquarters: Orange, CT, US · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  13. Sigma Theta Tau International Inc

    EIN 900264197 · Headquarters: Hamden, CT, US · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  14. Sigma Theta Tau International Inc

    EIN 901029452 · Headquarters: Waterbury, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  15. Sigmon Family Charitable Foundation

    EIN 866794470 · Headquarters: WEST HARTFORD, CT, USA · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-PF

  16. Sikh Education & Cultural Foundation Inc

    EIN 262752551 · Headquarters: Norwalk, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  17. Sikorsky Financial Credit Union

    EIN 060634736 · Headquarters: Stratford, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  18. Silas C Beers Uw Charitable Trust Uad

    EIN 776259773 · Headquarters: CORNWALL, CT, USA · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-PF

  19. Silver City Flying Club Inc

    EIN 736501521 · Headquarters: BEACON FALLS, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  20. Silver City Gun Club Inc

    EIN 061074630 · Headquarters: Meriden, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  21. Silver Paws Haven and Hospice

    EIN 824592319 · Headquarters: Windham, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  22. Silver Shield Association Inc

    EIN 061009211 · Headquarters: GREENWICH, CT, USA · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990

  23. Silver Spring Country Club Incorporated

    EIN 060536020 · Headquarters: RIDGEFIELD, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  24. Simmons Family Foundation Inc

    EIN 061409685 · Headquarters: GREENWICH, CT, USA · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-PF

  25. Simsbury Abc Program Inc

    EIN 237306464 · Headquarters: SIMSBURY, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  26. Simsbury Camera Club Inc

    EIN 066108179 · Headquarters: Simsbury, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  27. Simsbury Cemetery Association

    EIN 060536775 · Headquarters: SIMSBURY, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  28. Simsbury Community Band

    EIN 061070686 · Headquarters: Simsbury, CT, US · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  29. Simsbury Cultural Enrichment Committee

    EIN 272068682 · Headquarters: SIMSBURY, CT, US · Unknown & Unclassified · Latest available filing year: 2011 · Primary form: IRS Form 990-N

  30. Simsbury Friends for Music and the Performing Arts Inc

    EIN 223192101 · Headquarters: SIMSBURY, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  31. Simsbury Historical Society Inc

    EIN 066039934 · Headquarters: Simsbury, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  32. Simsbury Little League Baseball Inc

    EIN 521277711 · Headquarters: SIMSBURY, CT, USA · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-EZ

  33. Simsbury Radio Control Club

    EIN 271379414 · Headquarters: West Simsbury, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  34. Simsbury Volunteer Ambulance Assoc Inc

    EIN 066062402 · Headquarters: SIMSBURY, CT, USA · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990

  35. Singles Under Sail Inc

    EIN 223098471 · Headquarters: NEW CANAAN, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  36. Sister Cities International of Hartford Ct Inc

    EIN 223072541 · Headquarters: Plainville, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  37. Sisters of Charity of Our Lady, Mother of the Church

    EIN 391205444 · Headquarters: Baltic, CT, US · Unknown & Unclassified · Latest available filing year: 2016 · Primary form: IRS Form 990

  38. Sisters of Providence Care Centers Inc

    EIN 222541103 · Headquarters: HARTFORD, CT, USA · Unknown & Unclassified · Latest available filing year: 2022 · Primary form: IRS Form 990-EZ

  39. Skating Club of Fairfield County

    EIN 061458948 · Headquarters: STAMFORD, CT, USA · Unknown & Unclassified · Latest available filing year: 2020 · Primary form: IRS Form 990

  40. Ski Bears of Connecticut Inc

    EIN 061086128 · Headquarters: Norwalk, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  41. Skills Advancement Inc

    EIN 263707752 · Headquarters: Avon, CT, US · Unknown & Unclassified · Latest available filing year: 2011 · Primary form: IRS Form 990-N

  42. Sky Heart and Souls Inc

    EIN 830734672 · Headquarters: STONINGTON, CT, USA · Unknown & Unclassified · Latest available filing year: 2019 · Primary form: IRS Form 990-EZ

  43. Slater Library Corporation

    EIN 060664193 · Headquarters: JEWETT CITY, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  44. Slavic Heritage Institute Incorporated

    EIN 232256133 · Headquarters: Torrington, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  45. Sleeping Giant Day Care Inc

    EIN 061010027 · Headquarters: HAMDEN, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  46. Sleeping Giant Park Association Inc

    EIN 060946510 · Headquarters: Hamden, CT, US · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  47. Slovak Alliance of Greater Bridgeport Inc

    EIN 237445213 · Headquarters: Stratford, CT, US · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  48. Slovak Catholic Sokol

    EIN 237522608 · Headquarters: Bridgeport, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  49. Slovak Catholic Sokol

    EIN 237522795 · Headquarters: Shelton, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  50. Slovak Catholic Sokol

    EIN 237523019 · Headquarters: Torrington, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  51. Slovak Catholic Sokol

    EIN 237523070 · Headquarters: Shelton, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  52. Slovak Catholic Sokol 86

    EIN 237523093 · Headquarters: Torrington, CT, US · Unknown & Unclassified · Latest available filing year: 2019 · Primary form: IRS Form 990-N

  53. Slovak Gymnastic Union Sokol of the USA

    EIN 060538288 · Headquarters: Stratford, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  54. Slovak Gynastic Union Sokol of the USA 30

    EIN 060844195 · Headquarters: Brookfield, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  55. Smacna Connecticut Inc

    EIN 060618146 · Headquarters: GRANBY, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  56. Smaller Manufacturers Assn of Ct Inc

    EIN 510163148 · Headquarters: WATERBURY, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  57. Smalley Brothers Vfw Post6123

    EIN 066069925 · Headquarters: WINDSOR LOCKS, CT, USA · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990

  58. Smart Local Union No 40

    EIN 060532495 · Headquarters: ROCKY HILL, CT, USA · Unknown & Unclassified · Latest available filing year: 2020 · Primary form: IRS Form 990

  59. Smart Start Stem International

    EIN 472517112 · Headquarters: Cheshire, CT, US · Unknown & Unclassified · Latest available filing year: 2016 · Primary form: IRS Form 990-N

  60. Smile Anyway

    EIN 823498927 · Headquarters: BRANFORD, CT, US · Unknown & Unclassified · Latest available filing year: 2018 · Primary form: IRS Form 990-N

  61. Smith College Club of Greenwich Smith College Club of Greenwich &

    EIN 066078119 · Headquarters: Greenwich, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  62. Smith Cove Yacht Club Inc

    EIN 066178734 · Headquarters: Waterford, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  63. Smith Middle School Steering Committee and Pto

    EIN 832127959 · Headquarters: Glastonbury, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  64. Smocking Arts Guild of America Inc

    EIN 581839768 · Headquarters: Norwalk, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  65. Soccer Club of Newington Inc

    EIN 222534368 · Headquarters: NEWINGTON, CT, USA · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990

  66. Social Connections

    EIN 061445081 · Headquarters: Old Lyme, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  67. Societa Maria Ss Del Monte Carmelo Building Associ

    EIN 060540672 · Headquarters: Enfield, CT, USA · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990

  68. Society for Experimental Mechanics

    EIN 060763080 · Headquarters: BETHEL, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  69. Society for Preservation & Encourmt of Barbershop Quartet Singing Amer

    EIN 060624722 · Headquarters: Mystic, CT, US · Unknown & Unclassified · Latest available filing year: 2021 · Primary form: IRS Form 990-N

  70. Society for Preservation & Encourmt of Barbershop Quartet Singing Amer

    EIN 066074005 · Headquarters: Simsbury, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  71. Society for Preservation & Encourmt of Barbershop Quartet Singing Amer

    EIN 066082918 · Headquarters: Wallingford, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  72. Society for Preservation & Encourmt of Barbershop Quartet Singing Amer

    EIN 066082921 · Headquarters: Ledyard, CT, US · Unknown & Unclassified · Latest available filing year: 2020 · Primary form: IRS Form 990-N

  73. Society for Preservation & Encourmt of Barbershop Quartet Singing Amer

    EIN 066082922 · Headquarters: NAUGATUCK, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  74. Society for Preservation & Encrgmnt of Barbershop Quartet Singing Amer

    EIN 066074899 · Headquarters: Manchester, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  75. Society for Preservation & Encrgmnt of Barbershop Quartet Singing Amer

    EIN 066100159 · Headquarters: Newtown, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  76. Society for Reformation Research

    EIN 430888540 · Headquarters: CHESHIRE, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  77. Society for the Preservation and Encouragement of Barbershop Quart

    EIN 060851877 · Headquarters: Stratford, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  78. Society of American Magicians Magic Endowment Fund Inc

    EIN 222761202 · Headquarters: TOLLAND, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  79. Society of American Magicians Parent Assembly No 1 Inc

    EIN 136144414 · Headquarters: MIDDLETOWN, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990

  80. Society of Cosmetic Chemists Ct Chapter

    EIN 061136038 · Headquarters: ANSONIA, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  81. Society of Creative Arts Newtown

    EIN 060978466 · Headquarters: NEWTOWN, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  82. Society of Critical Care Medicine

    EIN 043282722 · Headquarters: Hartford, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  83. Society of Financial Service Professionals Connecticut Chapter

    EIN 066082276 · Headquarters: ROCKY HILL, CT, USA · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-EZ

  84. Society of Human Resource Management Inc

    EIN 912138360 · Headquarters: DARIEN, CT, USA · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-EZ

  85. Society of Manufacturing Engineers

    EIN 066084965 · Headquarters: Barkhamsted, CT, US · Unknown & Unclassified · Latest available filing year: 2018 · Primary form: IRS Form 990-N

  86. Society of Manufacturing Engineers

    EIN 066084966 · Headquarters: Waterbury, CT, US · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  87. Society of Manufacturing Engineers

    EIN 237150165 · Headquarters: Wallingford, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  88. Society of Orpheus & Bacchus

    EIN 061003238 · Headquarters: New Haven, CT, US · Unknown & Unclassified · Latest available filing year: 2022 · Primary form: IRS Form 990-N

  89. Society of Our Lady of Grace Inc

    EIN 061087760 · Headquarters: HARTFORD, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  90. Society of Plactic Engineers

    EIN 823181937 · Headquarters: Danbury, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  91. Society of Plastics Engineers

    EIN 066068798 · Headquarters: Hamden, CT, US · Unknown & Unclassified · Latest available filing year: 2022 · Primary form: IRS Form 990-N

  92. Society of Plastics Engineers

    EIN 133186178 · Headquarters: BETHEL, CT, US · Unknown & Unclassified · Latest available filing year: 2025 · Primary form: IRS Form 990-N

  93. Society of Plastics Engineers

    EIN 223049887 · Headquarters: Danbury, CT, US · Unknown & Unclassified · Latest available filing year: 2021 · Primary form: IRS Form 990-N

  94. Society of Plastics Engineers

    EIN 237241745 · Headquarters: Bethel, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

  95. Society of Plastics Engineers

    EIN 316050249 · Headquarters: DANBURY, CT, US · Unknown & Unclassified · Latest available filing year: 2020 · Primary form: IRS Form 990-N

  96. Society of Plastics Engineers

    EIN 510195173 · Headquarters: TRUMBULL, CT, US · Unknown & Unclassified · Latest available filing year: 2023 · Primary form: IRS Form 990-N

  97. Society of Plastics Engineers

    EIN 621431770 · Headquarters: Danbury, CT, US · Unknown & Unclassified · Latest available filing year: 2022 · Primary form: IRS Form 990-N

  98. Society of Plastics Engineers

    EIN 621500898 · Headquarters: DANBURY, CT, US · Unknown & Unclassified · Latest available filing year: 2020 · Primary form: IRS Form 990-N

  99. Society of Plastics Engineers

    EIN 742686513 · Headquarters: DANBURY, CT, US · Unknown & Unclassified · Latest available filing year: 2020 · Primary form: IRS Form 990-N

  100. Society of Plastics Engineers 15 Western New England Section

    EIN 510195187 · Headquarters: Vernon, CT, US · Unknown & Unclassified · Latest available filing year: 2024 · Primary form: IRS Form 990-N

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