The economy of London is dominated by service industries, particularly financial services and associated professional services, which have strong links with the economy in other parts of the United Kingdom (UK) and internationally. In addition to being the capital city of the United Kingdom, London is one of the world's leading financial centres for international business and commerce and is one of the "command centres" for the global economy.; ; ; ; ;

London is the most populous region, urban zone and metropolitan area in the United Kingdom.According to the European Statistical Agency, London is the largest Larger Urban Zone which uses conurbations and areas of high population as its definition. A ranking of population within municipal boundaries places London first. However, the University of Avignon in France claims that Paris is first and London second when including the whole urban area and hinterland, that is the outlying cities as well London had the fifth largest metropolitan economy in the world in 2011 according to the Brookings Institution. In 2024, GDP per capita of the City of London was £ or the largest in the world. The London fiscal surplus, £32.5 billion in 2016–17, mostly goes towards funding services in other parts of the UK.

London accounts for approximately 22 per cent of the UK's economic output. 841,000 private sector businesses were based in London at the start of 2013, more than in any other region or country in the UK. 18 per cent are in the professional, scientific and technical activities sector while 15 per cent are in the construction sector. Many of these are small and medium-sized enterprises.

Gross value added (GVA)

In 2023, London had GVA of £ and £ per capita.

GVA by borough

BoroughGVA (bil. £)GVA per head (£)Westminster and City of London204.021906,879Tower Hamlets44.834136,427Camden 40.213182,041Haringey and Islington31.14164,409Lewisham and Southwark30.37549,452Kensington and Chelsea and Hammersmith and Fulham 25.27775,761Hounslow and Richmond upon Thames 23.96648,879Hackney and Newham 21.89234,980Harrow and Hillingdon19.73133,875Merton and Kingston upon Thames 17.07928,618Lambeth15.38847,740Bexley and Greenwich13.03823,924Croydon 11.75729,560Barking & Dagenham and Havering 11.36523,173Redbridge and Waltham Forest11.06618,776Barnet 10.63926,934Brent10.08729,279Ealing 9.79526,096Wandsworth 8.69326,226Enfield 8.49925,957Bromley 8.28725,023 London 577.141 64,519

Service industries London shifted to a mostly service-based economy earlier than other European cities, particularly following the Second World War. A number of factors contribute to London's success as a service industry and business centre:

English being the native language and the dominant international language of business; its past role as the capital of the former British Empire; its position in Europe, since Europe has a population larger than that of the US, and a central time zone that allows London to act as a bridge between US and Asian markets; the Special Relationship between the United Kingdom and United States, and the United Kingdom's close relationships with many countries in Asia, Africa and the Middle East, particularly those in the Commonwealth of Nations; English contract law being the most important and most used contract law in international business; a business friendly environment (for example, relatively low taxes for corporations and non-domiciled foreign individuals; and, in the City of London, the local government is not elected by the resident population but instead by resident businesses – the City of London is a business democracy); good transport infrastructure particularly its aviation industry;; ; a high quality of life.; ; ; ;

Currently, over 85% (3.2 million) of the employed population of Greater London works in the service industries. Another half a million employees resident in Greater London work in manufacturing and construction, almost equally divided between the two.

Business districts

London has five major business districts: the City, Westminster, Canary Wharf, Camden & Islington and Lambeth & Southwark. One way to get an idea of their relative importance is to look at relative amounts of office space: Greater London had 26,721,000 m2 of office space in 2001.

+ Business district Office space (m2) Business concentration The City 7,740,000 Finance, broking, insurance, legal, fund managers, banking Westminster 5,780,000 Head offices, real estate, private banking, hedge funds, government Camden & Islington 2,294,000 Creative industries, finance, design, art, fashion, architecture, media Canary Wharf 2,120,000 Banking, media, legal Lambeth & Southwark 1,780,000 Accountancy, consultancy, local government

A useful guide to the distribution of wealth across London is the cost of renting office space. Mayfair and St. James's are historically and currently the most expensive areas – approximately £146 per sq ft per annum. The least expensive commercial districts are Waterloo & Southwark and East London Tech City, a new, but growing hub of start up technology companies, also known as Silicon Roundabout – approximately £65 per sq ft per annum.

Domestic and international corporate headquarters The London Stock Exchange is the most international stock exchange and the largest in Europe. More than half of the London Stock Exchange top 100 listed companies (the FTSE 100) and over 100 of Europe's 500 largest companies are headquartered in central London. Over 70% of the FTSE 100 are located within London's metropolitan area, and 75% of Fortune 500 companies have offices in London. According to research by Deloitte, "London has the most internationally diverse executive community in the world, attracting business leaders from 95 nationalities and with alumni working in 134 countries".

Financial services London's largest industry remains finance. It is the largest financial exporter in the world, and makes a significant contribution to the UK's balance of payments."Financial Services ", UK Trade & Investment, 11 May 2006. Retrieved 3 June 2006. In the 2017 Global Financial Centres Index, London was ranked as having the most competitive financial center in the world. However, in the 2018 ranking, London had lost that title to New York City. In the same ranking for 2020, London came second after New York City (with cities such as Shanghai, Tokyo, Hong Kong, Singapore, Beijing, San Francisco, Shenzhen and Zurich in the top 10). The City of London is home to exchanges, banks, brokers, investment managers, pension funds, hedge funds, private equity firms, insurance companies and reinsurance markets. London is notable as a centre of international finance where foreign participants in financial markets come to deal with one another. It is also home to the Bank of England, the second oldest central bank in the world, and the European Banking Authority, although the latter was moving to Paris in March 2019 following the Brexit referendum of 2016. Other key institutions are Lloyd's of London for insurance and the Baltic Exchange for shipping.;

A second financial district has developed at Canary Wharf to the east of the City, which includes the global headquarters of two of the world's largest banks, HSBC and Barclays, the rest-of-the-world headquarters of Citigroup and the headquarters of the global news service Reuters. London handled 36.7% of global currency transactions – an average daily turnover of US$1.85 trillion – with more US dollars traded in London than in New York, and more Euros traded than in every other city in Europe combined."Key facts ", Corporation of London. Retrieved 19 June 2006.European Central Bank (July 2017) "The international role of the euro". European Central Bank. p. 28.Chatsworth Communications (April 6, 2016) "London's leading position as a USD 2.2 trillion hub for FX trading would be harmed by a Brexit, according to poll of currency market professionals" . Chatsworth Communications. London is the leading centre for international bank lending, derivatives markets, money markets, international insurance, trading in gold, silver and base metals through the London bullion market and London Metal Exchange,; ; and issuance of international debt securities.

Financial services in London benefited from the UK's membership of the European Union (EU), although there were concerns following the decision of the United Kingdom to leave the EU. However, Britain’s exit from the EU in early 2021 (Brexit) only marginally weakened London's position as an international financial center (IFC).

The combination of lax regulation and London's financial institutions providing sophisticated methods to launder proceeds from criminal activity around the world, including those from the drug trade, makes the City a global hub for illicit finance and London a safe haven for the world's malfeasants, according to research papers and reports published in the mid-2010s.Dark money: London’s dirty secret Financial Times, 11 May 2016.London is now the global money-laundering centre for the drug trade, says crime expert The Independent, 4 July 2015.

Professional services

London is a leading global centre for professional services. Many different types of professional service providers are located in the city including the big four accountants and major management consulting firms. London is the headquarters for four of the world's six largest law firms and is a leading international centre for legal services.

Media

Media companies are concentrated in London, and the media distribution industry is London's second most competitive sector. , p19, Oxford Economic Forecasting on behalf of the Corporation of London. Published November 2005. Retrieved 19 June 2006. The BBC is a key employer, and other broadcasters also have headquarters around the city. Many national newspapers are edited in London: historically in Fleet Street in the City, but now dispersed across the capital. Soho is the centre of London's post-production industry. Hollywood's links with the United Kingdom are centred on London, and contribute billions to the economy.

Tourism

Tourism is one of London's prime industries. London is the most visited city in the world by international tourists with 18.8 million international visitors forecast in 2015, ahead of Bangkok (18.2 million) and Paris (16.1 million). Within the UK, London is home to the ten most-visited tourist attractions. Tourism employed the equivalent of 350,000 full-time workers in London in 2003,"London is the HR centre of opportunity in the UK ", PersonnelToday.com, 15 February 2005. Retrieved 3 June 2006. whilst annual expenditure by tourists is around £15bn."The Importance of Tourism in London ", Visit London. Retrieved 3 June 2006.

Technology A growing number of technology companies are based in London, notably in East London Tech City, also known as Silicon Roundabout. Investment in London's technology sector was $2.28 billion in 2015, 69 per cent higher than the $1.3 billion raised in 2014. Since 2010, London-based technology companies have collectively raised $5.2 billion of venture capital funding. A report by Ernst & Young highlighted the importance of London to the UK's FinTech industry in terms of availability of expertise and demand for services. London has also been named as the fastest growing technology hub in Europe, having over 100 unique tech companies with a value of $1 billion or more.

Retail London is a major retail centre, and in 2010 had the highest non-food retail sales of any city in the world, with a total spend of around £64.2 billion. The UK's fashion industry, centred on London, contributes tens of billions to the economy.

Manufacturing and construction