Paramedics and Highways officers are at the scene between Junction 14 for Stafford North and Junction 13 for Stafford South.
Highways England tweeted saying: "Lanes 1 and 2 (of 3) are blocked on the M6 Southbound between J14 Stafford North and J13 Stafford South due to a collision. Please use the contraflow lane in order to avoid this incident. Traffic officer and recovery en route.
"Traffic remains held at scene while ambulance asses injuries. Please use the contraflow lane in order to avoid this incident."