This list of built-up areas for England was compiled by the Office for National Statistics after the 2021 UK Census. Built-up area boundaries are defined and named by the ONS and do not necessarily coincide with other definitions that use the same names. (In ONS reports of the 2011 and 2021 censuses, many of these areas were called "built-up sub-areas" of larger urban areas; , the ONS has not defined a new nomenclature for each of the urban areas or released any data for them: for its reports on the 2021 Census, the ONS uses the term "Amalgamated Built-up Area" for urban areas but gives them a number rather than a name. )
The ONS has classified all built-up areas with a population of at least 200,000 as "major". Most are cities, with three large towns (Luton, Northampton and Reading) included. (Conversely, there are many settlements that have city status but do not reach the threshold.)
The ONS classified all built-up areas between 199,999 and 75,000 as large-sized, most include large towns or smaller cities.
The ONS classified all built-up areas between 75,000 and 20,000 as medium-sized, most are moderate towns with some exceptional cities or villages.
Hereford, Canterbury, Lancaster and Durham have city status, all others are towns and Rochester formerly had city status.
"Citypopulation.de" does not record areas with a population lower than Thundersley and South Benfleet.
Winchester, Lichfield and Chichester have city status between 30,000 and 49,700.
Truro officially has city status.