Emergency services were called to the scene at 1.02am after a Seat Ibiza and a Mercedes Actros lorry crashed on the southbound side of the carriageway between junctions 28 and 27.
The driver of the Seat, a man in his 20s from Liverpool, was pronounced dead at the scene.
Police say the HGV driver was not seriously hurt.
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The southbound M6 was closed for 10 hours whilst accident investigators worked at the scene and a diesel spillage was cleaned up.
You can read our full report on the crash and motorway closure here.
Lancashire Police are appealing for witnesses and dashcam footage to help investigators understand exactly how the crash happened.
Sgt David Hurst, of Lancashire Police’s tactical operations, said: "This collision has resulted in a man losing his life and my thoughts are with his loved ones at this extremely distressing time.
"We are now working to establish the full circumstances of the collision and I would ask any witnesses or anyone with dashcam footage which could assist us with our enquiries to please get in touch.”
Anyone with information is asked to email [email protected] or call 101, quoting log 0063 of July 1, 2021.