Area code 203 is a North American telephone area code that covers the southwestern part of Connecticut, and is overlaid with area code 475. The numbering plan area (NPA) 203 originally covered the entire state of Connecticut when the North American Numbering Plan was enacted in 1947. Today the numbering plan area stretches from Connecticut's western border, along its southern coast, to Madison, and north to Meriden. The region encompassed by 203 and 475 roughly corresponds to the Connecticut side of the New York metropolitan area.