Police were called around 12.45pm to reports of a one-vehicle collision close to Rivington Services going southbound.
A Kia Sportage car was travelling southbound when it left the carriageway and overturned.
Sadly the driver of the car, a woman in her 30s, suffered fatal injuries and was pronounced dead at the scene.
The road was closed for more than four hours while accident investigators attended the operation.
Police are appealing for witnesses following the fatal crash.
Officers are hoping other drivers may be able to provide information and urging any witnesses or motorists with dashboard mounted camera footage to come forward.
Sgt Chris Evans, of Lancashire Police’s Tactical Operations, said: “These are tragic circumstances and my thoughts are with the driver’s family and friends at this very sad and difficult time.
“A woman has lost her life and we are keen to establish exactly what has happened.
“We would encourage any witnesses, or any drivers with dashcam footage which might show the incident, to come forward if you can assist our investigation.”
Anyone with information can call police on 101 or email [email protected] quoting log 0643 of June 28.