| Name | Deductibility Code |
| 1905 Enterprises Inc. | -- |
| Alan Morton Foundation | 4 |
| Center for Creative Communities | -- |
| Community Action Southold Town Inc. | -- |
| East End Lighthouses Inc. | -- |
| East End Maritime Institute Inc. | -- |
| East End Seaport Museum and Marine | -- |
| Eastern Long Island Breast Cancer Resource Center Inc. | -- |
| Eastern Long Island Hospital Assoc Inc. | -- |
| Eastern Long Island Hospital Foundation | -- |
| Floyd Memorial Library | -- |
| Friends of Long Beach Orient State Park Inc. | -- |
| Greenport Youth Activities Inc. | -- |
| Gridiron Parents | -- |
| Holy Trinity Church | -- |
| Iglesia Alfa Y Omega | -- |
| John C Dunphy Private Foundation Inc. | 4 |
| North Folk Unitarian Universalist Fellowship | -- |
| North Fork Housing Alliance Inc. | -- |
| North Fork Women for Women Fund | -- |
| Peconic Health Corporation | -- |
| Peconic Landing at Southold Inc. | 1 |
| Railroad Museum of Long Island | -- |
| Robert L Perry Jr Development Corp | -- |
| San Simeon by the Sound Center for Nursing and Rehabilitation | -- |
| San Simeon by the Sound Inc. | -- |
| Spay Alter Vaccinate Every Stray Inc. | -- |
| Suffolk County Village Officials Association Inc. | -- |
| William Glasgow Thompson Charitable Fund Inc. | -- |
| Wish Factory Inc. | -- |
| Wr Hr Corporation | -- |