The area code 660 is located in the northern and western parts of the state of Missouri. It was created on October 12, 1997, in a split of the 816 area code. The area code covers outlying regions such as Sedalia, Warrensburg, Moberly, Marshall, Maryville, Kirksville, and other small towns and communities in that region. It is the only area code that serves the area. The area code touches 39 different counties, including Pettis, Johnson, Adair, Saline, Nodaway, Lafayette, Randolph, Henry, Cooper, and Macon counties.