Area Codes
| 660 | Missouri (Marshall, Sedalia, Macon, Trenton, Maryville, Bethany and north central Missouri) | More information at: Area Code 660 Phone Number Blocks
| 660 | Missouri (Marshall, Sedalia, Macon, Trenton, Maryville, Bethany and north central Missouri) | More information at: Area Code 660 Phone Number Blocks