Many of those Pubs in Middlesex may already be listed as part of London, for instance in Stoke Newington. The listings here are a little out of date; and the Middlesex pub history section is to be remodelled on the later directory in 1926 and 1937. The Middlesex section is largely listed by Directories rather than census, therefore many pubs in the Hillingdon census may be listed under Uxbridge, Cowley or West Drayton / Yiewsley.
Hampton, Hanwell, Hammersmith, Hampstead, Hanworth, Harefield, Harlesden (see Willesden) , Harlington, Harmondsworth, Harrow (includes Wembley, Sudbury, Alperton etc), Hatch End, Hayes (Southall), Hendon, Heston, Highgate, Hillingdon, Hornsey, Hounslow,
The Middlesex Genuki page was incredibly helpful in deciding where to list an area.