Population density of London boroughs (and the City of London which is a ceremonial county) in 2021 varied from 2 197 per square km in Bromley to 15 802 per square km in Tower Hamlets. Population density of the whole London was 5 598 per square km in 2021.
More densely populated boroughs are located in the inner part of London. However, the central City of London has a low population density of only 2971 per square km. This is because the City is dominated by commercial buildings where working day population might reach between 500 000 to 1 million.
Source: Office for National Statistics