Williamstown City Area Code List
| Area Codes | Country | State | City | Time Zone | Operating |
|---|---|---|---|---|---|
| 304 | US | West Virginia - VA | Williamstown | Eastern | Details |
| 315 | US | New York - NY | Williamstown | Eastern | Details |
| 413 | US | Massachusetts - MA | Williamstown | Eastern | Details |
| 573 | US | Missouri - MO | Williamstown | Central | Details |
| 802 | US | Vermont - VT | Williamstown | Eastern | Details |
| 856 | US | New Jersey - NJ | Williamstown | Eastern | Details |
| 859 | US | Kentucky - KY | Williamstown | Eastern | Details |