Big Bend is an unincorporated community in Calhoun County, West Virginia, United States. It lies along West Virginia Route 5 northwest of the town of Grantsville, the county seat of Calhoun County, alon…Big Bend is an unincorporated community in Calhoun County, West Virginia, United States. It lies along West Virginia Route 5 northwest of the town of Grantsville, the county seat of Calhoun County, along the Little Kanawha River. Its elevation is 682 feet. It has a post office with the ZIP code 26136.