Area code 253. From Wikipedia, the free encyclopedia. Area code 253 is a telephone dialing code in Washington for the cities south of Seattle and of the southern Puget Sound area, centered at Tacoma and extending to include the areas around Gig Harbor, Auburn, and Roy.It currently serves the western half of Pierce County, Washington.he area code went into service on April 27, 1997, as part of a three-way split of area code 206.