Area code 203 covers the Southwestern part of Connecticut. The area code stretches from the New York border past the city of New Haven and ends just south of Hartford. Major cities in the 203 area code include: Bridgeport, Danbury, Greenwich, Meriden, Milford, New Haven, Norwalk, Stamford, and Waterbury. The CT Public Utility commission has proposed an area code overlay for the 203 area code. The new area code assigned is 475. A date for the new overlay area code to be implemented has yet to be assigned.
Areacode 413 is the areacode for Western Massachusetts.
It is the largest areacodearea by land area covered in the state, extending from the western stateline to west of Worcester County and covering from border to border north to south.
As Western Massachusetts has no overlay areacode (in other words it has only one areacode), it is the only part of Massachusetts which does not require 10 digit dialing.