On 8 February 1960, it was announced that a bypass would be built, including the route south to the B6403 at Colsterworth. Robert McGregor and Sons Ltd of Manchester would build the road for £1,856,009. (The company went on to build Newark bypass in 1964.) The bridges were built by Simon Carves of Cheadle Hulme. It was formally opened on 10 October 1962 by James Heathcote-Drummond-Willoughby, 3rd Earl of Ancaster, then the Lord Lieutenant of Lincolnshire (from 1950 to 1975). He was married to the (only) daughter of Nancy Astor.