203 Area Code
The 203 area code covers the southwestern part of Connecticut. Residents from Fairfield (except the city of Sherman), New Haven, and part of Litchfield counties used area code 203. 475 area code will soon overlaid with 203 area code, but the exact date for implenting the new area code has not yet been determined.
| Ansonia, CT | Beacon Falls, CT | Bethany, CT |
| Bethel, CT | Bethlehem, CT | Botsford, CT |
| Branford, CT | Bridgeport, CT | Brookfield, CT |
| Cheshire, CT | Cos Cob, CT | Danbury, CT |
| Darien, CT | Derby, CT | East Haven, CT |
| Easton, CT | Fairfield, CT | Georgetown, CT |
| Greens Farms, CT | Greenwich, CT | Guilford, CT |
| Hamden, CT | Hawleyville, CT | Madison, CT |
| Meriden, CT | Middlebury, CT | Milford, CT |
| Monroe, CT | Naugatuck, CT | New Canaan, CT |
| New Fairfield, CT | New Haven, CT | Newtown, CT |
| North Branford, CT | North Haven, CT | Northford, CT |
| Norwalk, CT | Old Greenwich, CT | Orange, CT |
| Oxford, CT | Prospect, CT | Redding, CT |
| Redding Center, CT | Redding Ridge, CT | Ridgefield, CT |
| Riverside, CT | Roxbury, CT | Sandy Hook, CT |
| Seymour, CT | Shelton, CT | Sherman, CT |
| South Britain, CT | Southbury, CT | Southport, CT |
| Stamford, CT | Stevenson, CT | Stratford, CT |
| Trumbull, CT | Wallingford, CT | Waterbury, CT |
| West Haven, CT | Weston, CT | Westport, CT |
| Wilton, CT | Wolcott, CT | Woodbridge, CT |
| Woodbury, CT |