A prototype was built in 1949, before production commenced in 1952.

[1] The first 25 were built to the maximum permissible length of 8.4 metres (28 ft) for London Transport before maximum length for PSVs increased to 9.1 metres (30 ft).

[2][3] Over 2,600 were built, London Transport was the largest operator, purchasing over 700, while British European Airways purchased 64 as coaches.

[4][5] Production for UK market finished in 1955 with the introduction of the AEC Reliance but it remained in production for export markets until the 1960s.

[2] Media related to AEC Regal IV at Wikimedia Commons