Two lorries are involved in the collision at the junction with the B1394, Sleaford Road.
There are long delays as a result.
A Lincolnshire Fire and Rescue Service spokesman added that a crew from Donington had attended at 5.31am to soak up a small fuel leak using absorbent granules and provided lighting for the emergency services workers on the scene.
Sleafordian Coaches posted: "This may cause a few of our routes coming in and out of that area to be slightly late but we are doing all we can to ensure all disruption will be kept to a minimum. We apoligise for any inconvenience this may cause.
"There is also very heavy traffic on the A17 approaching Holdingham roundabout - This has caused late runnings to our ROUTE F, SLE6 NEWARK B ROUTE and 3497. Please bear with us and we will be with you as soon as possible."