During its existence, there was a long-term decline in population as more residents moved into the outer suburbs; there were periodic reviews of the local government structures in the greater London area and several failed attempts to expand the boundaries of the county.

These included the loss of the Alexandra Park exclave to Middlesex, gaining South Hornsey in return, and the transfer of Penge to Kent.

The Metropolis Management Act 1855 revolutionised and amalgamated much of local government across an identical, newly formed, area.

This reform created an indirectly elected Metropolitan Board of Works which initially built and maintained infrastructure for the metropolis, including modern sanitation.

[3] Over time the board gained more functions and became the de facto local authority and provider of new services for the London area.

The board operated in those parts of the counties of Middlesex, Surrey and Kent that had been designated by the General Register Office as "the Metropolis" for the purposes of the Bills of Mortality.

[6] Ultimately, the Local Government Act 1888 and the introduction of county councils in England provided the mechanism for creating a territory and authority encompassing the expanded London area.

In practice, the county council had very little authority over the ancient City, with some powers over drainage, roads, fire brigade, embankment of the river and flood prevention.

[1] In common with the rest of the country, the 1888 Act provided no reform of lower-tier authorities and the county was, initially at least, administered locally by a series of parish vestries and district boards.

§The Metropolitan Boroughs of Camberwell, Deptford, Fulham, Greenwich, Hackney, Hammersmith, Hampstead, Lewisham, Poplar, Stoke Newington, Wandsworth and Woolwich.