It starts at SR 256 in Pickerington, and ends at US 22 near Mount Perry.

At a length of 37.79 miles (60.82 km), the route is located parallel to Interstate 70 in Fairfield and Perry counties east of Columbus, the state capital.

Route 204A runs south from I-70 to SR 204, connecting the two parallel roads.

Route 204A also serves as the off ramp for I-70 until it becomes Taylor Road and intersects SR 204.

A No Outlet sign is posted because the I-70 off ramp is southbound only and there is no access northbound to I-70.