The collision happened around 2.30pm on Sunday afternoon and involved two cars, a silver Peugeot 206 and a silver Renault Clio
The northbound carriageway was closed between Colsterworth and Stamford for much of the afternoon and evening.
A 42 year-old man from Mansfield died in the collision. The deceased was the driver of the Peugeot. His next of kin have been informed.
Police are appealing for witnesses, particularly drivers who were in the slow-moving southbound carriageway, who saw the Peugeot and the Clio being driven prior to the collision, or who witnessed the collision.
Anyone with information should call 101, quoting incident number 245 of 9th July.