Starting December 12, 2009, Connecticut area code 203 covering cities such as Bridgeport, New Haven or Stamford wil be overlayed by the new area code 475. The new code will cover the exact same area currently covered by area code 203.
As a result of the introduction of this new area code, CT residents of these areas will be required to dial 10 digit numbers for local calls. There is a permissive dialing period allowing both 7 and 10 digit dialing starting on May 16, 2009 and ending on November 14, 2009. Starting Nov. 14 all calls within the 203/475 overlay complex should be dialed using 10 digit dialing.