List of Connecticut area codes

This is a list of area codes in Connecticut:

In 1999, Connecticut announced that two additional codes may be implemented when needed: 475, overlaying 203; and 959, overlaying 860. In March 2009, NANPA announced area code 475 to overlay 203 in December 2009. Effective November 14, 2009, all calls originating from area code 203 or 860 must be dialed with 10 digits beginning with the area code, including calls within the same area code.

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