State: Connecticut
County: Middlesex
| ZIP | TOWN/CITY | STATE | COUNTY | POP | POP FOR COUNTY |
| 06416 | Cromwell | CT | Middlesex County | 13,910 | 74319 |
| 06455 | Middlefield | CT | Middlesex County | 3,077 | |
| 06457 | Middletown | CT | Middlesex County | 46,511 | |
| 06459 | Middletown | CT | Middlesex County | 195 | |
| 06480 | Portland | CT | Middlesex County | 9,322 | |
| 06481 | Rockfall | CT | Middlesex County | 1,304 | |
GROUP IS OPEN
| ZIP | TOWN/CITY | STATE | COUNTY | POP | POP FOR COUNTY |
| 06409 | Centerbrook | CT | Middlesex County | 860 | 88098 |
| 06412 | Chester | CT | Middlesex County | 4,234 | |
| 06413 | Clinton | CT | Middlesex County | 12,928 | |
| 06414 | Cobalt | CT | Middlesex County | 134 | |
| 06417 | Deep River | CT | Middlesex County | 4,480 | |
| 06419 | Killingworth | CT | Middlesex County | 6,392 | |
| 06422 | Durham | CT | Middlesex County | 7,221 | |
| 06423 | East Haddam | CT | Middlesex County | 5,374 | |
| 06424 | East Hampton | CT | Middlesex County | 12,744 | |
| 06426 | Essex | CT | Middlesex County | 3,401 | |
| 06438 | Haddam | CT | Middlesex County | 2,906 | |
| 06441 | Higganum | CT | Middlesex County | 5,011 | |
| 06442 | Ivoryton | CT | Middlesex County | 2,343 | |
| 06456 | Middle Haddam | CT | Middlesex County | 259 | |
| 06469 | Moodus | CT | Middlesex County | 2,802 | |
| 06475 | Old Saybrook | CT | Middlesex County | 10,090 | |
| 06498 | Westbrook | CT | Middlesex County | 6,919 |