London has a population of approximately 9.1 million people as of 2025, making it the largest city in the United Kingdom and Western Europe. When the surrounding commuter belt is included, the wider metropolitan area is home to roughly 14.3 million residents, ranking London among the largest urban agglomerations on the continent and a magnet for migration from across Britain and the world.
How Many People Live in London?
The figure of 9.1 million refers to Greater London, the administrative region governed by the Greater London Authority and divided into 32 boroughs plus the historic City of London. This area covers 1,572 square kilometres, giving an average density of around 5,790 people per square kilometre — far higher than any other part of the UK. To put the scale in perspective, London's population is larger than that of Scotland, Wales, and Northern Ireland combined.
Beyond the official boundary, millions more live in the connected towns and suburbs of the South East. The London commuter belt stretches into Surrey, Kent, Essex, Hertfordshire, and Berkshire, pushing the functional metropolitan population to about 14.3 million. This wider region generates close to 30% of the United Kingdom's economic output, underlining how much of the country's life is concentrated around its capital.
Population Growth and Recent Trends
London's modern story is one of dramatic decline followed by remarkable recovery. The city reached an early peak of about 8.6 million in 1939, then lost more than two million residents over the following half-century as wartime damage, deindustrialisation, and suburban flight drove people outward. By 1991 the population had fallen to roughly 6.8 million.
Since the 1990s the trend has reversed sharply. A booming service economy, large-scale international migration, and the regeneration of former industrial districts have all fuelled steady growth. London regained its 1939 peak around 2015 and has continued climbing since. The COVID-19 pandemic caused a brief dip as remote work prompted some residents to leave for cheaper regions, but numbers rebounded quickly once international arrivals resumed. Demographers project the population could approach 10 million by the mid-2030s, driven by net migration and a relatively young, fertile population.
The Boroughs: A City of Many Cities
London's 32 boroughs differ enormously in size, density, and character. The most populous include Barnet and Croydon, each home to roughly 390,000 to 400,000 people, alongside Newham at about 380,000. At the other extreme sits the City of London — the famous "Square Mile" financial district — whose resident population is only around 8,600, even though more than half a million workers pour in during business hours.
Inner boroughs such as Tower Hamlets, Hackney, and Islington tend to be denser, younger, and more diverse than the leafier outer boroughs like Bromley, Havering, and Hillingdon, which feel distinctly suburban. Tower Hamlets is the most crowded, with a density of roughly 15,700 people per square kilometre — comparable to the busiest neighbourhoods of New York or Hong Kong. This patchwork means that "London" is really a federation of dozens of distinct communities, each with its own high streets, accents, and identities.
Diversity and Demographics
London is one of the most diverse cities on Earth. Roughly 37% of its residents were born outside the United Kingdom, and more than 300 languages are spoken across the capital. The largest foreign-born communities trace their origins to India, Poland, Romania, Bangladesh, Nigeria, and Pakistan. No single ethnic group forms a majority: around 37% of Londoners identify as White British, with the remainder spread across a wide range of White, Asian, Black, mixed, and other backgrounds.
This mix gives the city a famously young profile. London's median age is about 35, several years below the UK average of around 40, reflecting both immigration and higher birth rates than the country as a whole. That youthfulness powers the city's labour market and cultural energy, from the food markets of Brick Lane and Brixton to the Notting Hill Carnival. Yet London is also a place of stark contrasts, with some of Europe's wealthiest districts in Kensington and Chelsea sitting close to areas of real deprivation. Average house prices well above £500,000 — roughly double the national figure — capture the pressures of life in such a crowded, sought-after city.
Why London Keeps Growing
Several forces sustain London's expansion. As a leading global financial centre alongside New York and Tokyo, it offers an unusually deep pool of high-value jobs. Its universities draw hundreds of thousands of domestic and international students. International migration adds a large share of newcomers each year, while the city's relatively young population means births comfortably outpace deaths. Together these factors keep the capital growing even as parts of the wider UK stagnate or shrink.
Frequently Asked Questions
What is the population of London in 2025?
Greater London has a population of approximately 9.1 million people in 2025. Including the surrounding commuter belt, the wider metropolitan area holds around 14.3 million residents.
Is London the biggest city in Europe?
London is the largest city in Western Europe and one of the largest on the continent. Some Eastern European and Eurasian metropolitan areas, such as Istanbul and Moscow, are larger depending on how their boundaries are measured.
How densely populated is London?
Greater London averages about 5,790 people per square kilometre, though this varies hugely by borough. Tower Hamlets reaches roughly 15,700 per square kilometre, while outer suburban boroughs are far less crowded.
How many boroughs does London have?
London is made up of 32 boroughs plus the City of London, each functioning as a local authority with its own council and distinct community character. If you enjoy learning facts like these, try our geography games.
