The London Routemaster bus is probably the most famous design of bus ever produced. Over 2,760 were built between 1954 and 1968 and hundreds of them still operated in all day service in the capital until 2005, even though large numbers had been withdrawn between 1982 and 1988. During this period many were snapped up by other operators, particularly after deregulation of the bus industry in 1986. The new privatised companies saw conductor operated RMs as giving them a competitive edge to win passengers.
The newly formed Blackpool Transport eventually bought 12. No. 521 was taken on trial in January 1986 before more were purchased. Initially it ran in London red, but in May it was the first to receive the 1930's red and white livery chosen for the Routemasters.
At first, 521 and other RMs were dedicated to service 12 to St.Annes to compete with Fylde Transport. However, as other Blackpool town services became one man operated the 12 followed suit and the RMs were confined to summer use on the Promenade. After the 1994 season they retired to depot but came out in 1996 for a park and ride service to Lytham Golf Championships. 521, with 522-524, then continued to be used for the Zoo service for the rest of that year.
In 1997, Blackpool Transport sold the RMs to Reading Mainline but following that company’s take-over by Reading Transport, 521 passed to Walkabout Inns as a promotional bus. When surplus to their requirements it returned to Blackpool as part of the LTT collection. Over the winter of 2003/2004 it was re-panelled and paint stripped by LTT volunteers, being repainted in its vintage style red and white livery in June 2004. In November 2006 the bus was upgraded back to a class VI psv standard and was also used by the Trust's partner company for wedding hires and other events.
In December 2016, "521" was repainted back into 1970s style London red and white livery, allowing the bus to be more useful on wedding hires.