Bellingham is the county seat of Whatcom County in the U.S. state of Washington. It lies 21 miles south of the U.S.–Canada border, betwe…Bellingham is the county seat of Whatcom County in the U.S. state of Washington. It lies 21 miles south of the U.S.–Canada border, between Vancouver, British Columbia, 52 miles to the northwest and Seattle 90 miles to the south.