| County Name | Population | State | Rank |
|---|---|---|---|
| Fairfield County | 916,829 | Connecticut | 1 |
| Hartford County | 894,014 | Connecticut | 2 |
| New Haven County | 862,477 | Connecticut | 3 |
| New London County | 274,055 | Connecticut | 4 |
| Litchfield County | 189,927 | Connecticut | 5 |
| Middlesex County | 165,676 | Connecticut | 6 |
| Tolland County | 152,691 | Connecticut | 7 |
| Windham County | 118,428 | Connecticut | 8 |