To figure out how many people live in London, we can look at the most recent census. The census is taken every 10 years, with the last one completed on March 27th 2011. Based on the 2011 numbers, the population of London stands at 8,173,941. London's population makes it the largest city in the United Kingdom. The second largest city in the UK - Birmingham - has a population of 1.1 million. London is also the largest city in the European Union and is more than twice as large as its nearest rival, Berlin.