The Gatwick Interchange is a signal controlled roundabout forming junction 9 of the M23, connecting it to M23 Gatwick Spur. Built as part of the original M23 it is relatively unchanged save for the addition of traffic lights. The junction was opened with the rest of the M23 in 1975 including the spur. During 2019 the M23 was upgraded to a smart motorway between J8 with the M25 J7 at Merstham and J10 with the A2011 and A264. This upgrade turned the hard shoulder into a permanent 4th running lane and included alterations to this junction.