What was Greater London's population in the 2021 census?

Greater London’s population in the 2021 census was 8,799,800. This is the rounded census total for the Greater London region, which includes the City of London and 32 London boroughs.

The Office for National Statistics reported the 2021 figure as a 7.7% increase from 2011, when London’s population was about 8.17 million. The census measured usual residents on 21 March 2021, during the COVID-19 pandemic, rather than everyone temporarily present in the capital.

A precision trap explains why some sources show a slightly different number: later detailed tables give an unrounded total of roughly 8.8 million, while the initial regional release rounded the figure to the nearest 100. The answer used here matches that standard published presentation.

Greater London is not the same as the London metropolitan or built-up area. Those wider areas extend beyond the administrative boundary into surrounding counties and therefore can produce substantially different population totals.