From here the 18 and 18B ran daily, the 18A on Mondays to Saturdays and the 18C on Sundays, via Paddington and Harrow Road to Harlesden, where the 18A continued to Park Royal.

The 18C Sunday extension into the centre was also withdrawn; the 18 was cut back to Wembley Empire Pool on Mondays to Saturdays, but was diverted at Wealdstone to serve Canons Park and Edgware, with a peak hours and Sundays extension to provide a service to Aldenham Works.

The 18C was renumbered to 92 on 14 June 1944, with a 92A variant running to Wembley Trading Estate at certain times of the week.

The former 18A was reintroduced at peak hours, running between Acton and Paddington Green via a slightly different route.

[6] On 13 November 2010, route 18 was converted back to double deck operation as part of the Mayor of London's policy to replace the O530Gs.

[8] On 22 June 2013, route 18 was included in the sale of First London's Willesden Junction garage to Metroline.