Area code 425 is a telephone area code in the North American Numbering Plan (NANP). It is used in the state of Washington in the United States. It was established on April 27, 1997 on the same date as another Washington state area code, 253, as a split from area code 206. It covers cities like Bellevue, Kirkland, Redmond, Bothell, Issaquah, and Lynnwood.