| Name | Deductibility Code |
| Cleve Gray Foundation | 4 |
| Lake Waramaug Task Force Inc. | -- |
| Shei Rah Foundation Inc. | 4 |
| The Webster Society Inc. | -- |
| Warren Affordable Housing Corporation | -- |
| Warren Historical Society Inc. | -- |
| Warren Land Trust Inc. | -- |
| Warren Public Library Inc. | -- |
| Warren Volunteer Fire Company Inc. | 6 |