The A1(M) heading northbound between the M1 junction 47 and the A1(M) junction 44 have been closed due to a crash.
National Highways: Yorkshire said there had been a 'multi-vehicle' collision.
The crash happened at around 9.30am.
National Highways Yorkshire tweeted: "There are currently 3 lanes of (4) closed on the #A1M north between the #M1 J47 and #A1M J44 due to a multi-vehicle collision. Emergency services are at scene along with #TrafficOfficers who are assisting with traffic management. Please allow extra time for your journey."
The road fully reopened at around 11.45am, but there were delays of up to 50 minutes, with traffic backing up for five miles along the motorway.