1 May 2024 - 11min Read

Power up your knowledge

Biggest UK companies

Although these UK firms are not on the scale of some US behemoths, there are plenty of UK companies that will be familiar to traders around the world. They are of particular importance to traders because many significantly influence their sectors and marketplaces. These companies are traded on the London Stock Exchange and included in the FTSE100, an index of the top 100 UK companies as measured by market capitalisation.


Key takeaways

  • Why knowing the biggest UK companies is important for traders?
  • What are the biggest UK companies by revenue and market capitalisation?
  • What are the biggest construction companies in the UK?
  • What are the biggest energy companies in the UK?
  • What are the biggest insurance companies in the UK?

Marc Aucamp

Content Writer

Liked this article? Share now on socials

Why knowing the biggest UK companies is important for traders?

The United Kingdom has one of the world's largest economies and is home to many large-cap companies. All stock traders, especially those in the UK, should be aware of the biggest businesses headquartered there. These businesses have had far-reaching influence both within and outside of the UK. Paying attention to the leaders of these corporations and analysing the price movements of their respective stocks can help traders gauge the health of the UK economy. This, in turn, can help traders use their operational expertise to comprehend the markets better and generate trading ideas for themselves.

The biggest UK companies by market cap

Here are some of the biggest UK companies by market capitalisation:

AstraZeneca (LSE: AZN) 

AstraZeneca, the pharmaceutical and science firm best known for its part in creating the Oxford-AstraZeneca Covid-19 vaccine, is currently the UK's largest company by market capitalisation. The vaccine was developed in cooperation with Oxford University.

AstraZeneca has interests in several medical treatment categories, including the cardiovascular, brain cancer, respiratory, and gastrointestinal fields.

It was established in 1999 by merging Sweden’s Astra AB and the British Zeneca Group. The business is still listed on the Swedish Nasdaq, in addition to the London Stock Exchange and the Nasdaq US. Its headquarters are located at the Cambridge Biomedical Campus in Cambridge, UK. 

AZN has long been a leader in the pharmaceutical industry, but it did not become the largest business in the UK until it participated in the Covid-19 vaccine.

Shell (LSE: SHEL)

Shell has long been one of the most important listed companies on the London Stock Exchange (LSE), as it remains one of the world's largest energy and gas suppliers. However, a sluggish rebound from the mass market selloff at the start of 2020 caused the company to relinquish its top position to AZN.

Shell is a member of the energy supermajors, which includes BP, TotalEnergies, and ExxonMobil. In terms of income, it is second only to ExxonMobil among the supermajors.

Shell, like AstraZeneca, was founded by merging a continental business, the Royal Dutch Petroleum Company, and a British company, the "Shell" Shipping and Trading Company. The business is listed on the London Stock Exchange (LSE), Euronext Rotterdam, and the New York Stock Exchange (NYSE) 

Unilever (LSE: ULVR)

Unilever is a worldwide consumer products business and is regularly in the top five largest publicly traded companies by market capitalisation in the United Kingdom. It is headquartered in London and offers a wide range of goods across three main divisions:

  • Food and beverages
  • Personal health services
  • Personal care and beauty

Ben & Jerry's, Dove, Knorr, Lynx (Axe), Hellman's, and Wall's are among its best-known brands. Unilever's goods are distributed worldwide.

Unilever had offices in both the United Kingdom and the Netherlands until 2020. It is now traded on the London Stock Exchange, with subsidiary listings on Euronext Rotterdam and the New York Stock Exchange.


HSBC is the UK's most valuable bank by market capitalisation and Europe's largest bank by assets. Initially located in Hong Kong (and known as the Hong Kong and Shanghai Banking Company), HSBC has been headquartered in London since 1991.

HSBC shares are traded on both the London and Hong Kong stock exchanges, with subsidiary listings on the NYSE and the Bermuda Stock Exchange.

The bank is divided into three sections:

  • Global commercial banking
  • Financial services to corporates, governments, and institutions globally
  • Personal finance and wealth management

Asset management and personal banking generate the majority of the company's revenues and serve over 50 million clients globally.


BP, another oil supermajor, has been one of the top ten largest corporations quoted on the LSE for many years. Initially known as the Anglo-Persian Oil Corporation and then British Petroleum, the firm is now known simply as BP and is also amongst the world's top ten energy producers ranked by revenue per second. 

Like the other big companies discussed here, BP is traded on multiple exchanges, including the Frankfurt Stock Exchange and the New York Stock Exchange. In 2013, BP acquired a roughly 20% share in Rosneft, the Russian energy colossus. 

Diageo (LSE: DGE)

Diageo is a London-based alcoholic beverage corporation with over 200 brands, and sales across 180 countries, focusing on Scottish whisky and other spirits. It is traded on the London Stock Exchange, with a secondary float on the New York Stock Exchange. Diageo produces 40% of all Scottish whisky.

Among the company's trademarks are the following:

  • Johnny Walker
  • Guinness
  • Smirnoff
  • Baileys
  • Gordon's
  • Tanqueray
  • Pimms 

Diageo also has a 34% interest in LVMH's Moet Hennessy subsidiary.

British American Tobacco (LSE: BATS)

British American Tobacco is a UK cigarette and tobacco company established in 1902. It is the world's biggest cigarette business by revenue, with several major combustible brands, including Camel, Lucky Strike, Pall Mall, and Dunhill.

BATS has also entered the non-combustible smoking sector with devices like Vype, Vuse, and Glo. It has even made steps to expand into the legal marijuana market, acquiring a 20% share in OrganiGram, a Canadian manufacturer, in 2021.

BATS shares are traded on the Johannesburg Stock Exchange (JSE) and the New York Stock Exchange (NYSE) in addition to the LSE. 

Rio Tinto (LSE: RIO)

Rio Tinto is an Anglo-Australian mining firm that is the world's third-largest producer after Glencore and BHP. It has headquarters in London and Melbourne and is traded on the LSE and the Australian Securities Exchange (ASX).

RIO is currently the largest company in the UK when measured by profit, making $21 billion in 2022 on $63 billion in sales.

The business mines various materials, including iron ore, copper, aluminium, uranium, and gemstones. It also refines certain materials.

Glencore Inc. (LSE: GLEN)

Glencore is an unusual business. It is listed as a miner, and while it is a major diversified commodities and natural resources producer, it is also the world's biggest commodity trader. As it describes itself: ‘The Group's operations comprise around 150 mining and metallurgical sites, oil production assets and agricultural facilities’. However, it isn't entirely British; it is located in Switzerland, though its energy and gas operations are based in London. 

The GLEN equity is traded on both the LSE and the Johannesburg Stock Exchange. Glencore International combined with Xstrata in 2013 to create the business.


GSK, formerly GlaxoSmithKline, is a pharmaceutical and science corporation based in London. It was higher among the top UK businesses until a demerger of its consumer healthcare segment (into a new company, Haleon) in July 2022 reduced its market value.

GlaxoSmithKline remains one of the world's top ten pharmaceutical firms. It has developed several medications designated as important by the World Health Organization, including amoxicillin, pyrimethamine, and mercaptopurine.

The markets are moving.

Start trading now.

Get startedarrow-icon

The biggest UK companies by revenue

Market capitalisation, which is calculated by multiplying a company’s share price by the number of shares in circulation, is not the only gauge of a company's size and health. Revenue, or sales, is another useful measure, and this can lead to a different assessment from considering market capitalisation alone.  

Tesco (LSE: TSCO)

Tesco is currently in the top 30 of the UK's largest companies in terms of market capitalisation. But it is regularly in the top five when measured by revenue. The difference may be explained in part by Tesco's poor profit margin. Its £84 billion in sales converted to a profit of £2 billion in 2022, ranking the business 15th in terms of the UK's largest corporations by the bottom line.

Tesco's profits have shrunk due to fierce rivalry in the grocery industry, which has been fueled in part by ultra-low-cost newcomers such as Aldi and Lidl, as well as high inflation, which has made products more costly, squeezing Tesco’s margins. Despite this, Tesco remains one of the most important companies in the UK, employing over 230,000 people.

Aviva (LSE: AV) 

Another interesting example is the insurance giant Aviva. In terms of market capitalisation, it currently sits below the top 40 companies listed on the LSE. In 2022 the company posted revenues of £ 2.7 billion.  This represented a sharp increase in sales from the previous year, although profits fell that year, further reducing the company’s profit margin.

The biggest construction companies in the UK

Berkeley Group (LSE: BKG)

Berkeley Group is the largest construction business in the United Kingdom in terms of market capitalisation. 

Barratt Developments (LSE: BDEV)

Barratt Developments is the FTSE's second-most-valued construction company in the UK. It holds three home construction market brands: Barratt Homes, David Wilson Homes, and Barratt London.

Persimmon (LSE: PSN)

Persimmon is another UK construction company that can be found near the bottom of the FTSE 100. Persimmon has acquired several companies over the years, including Beazer Homes and Westbury.

The biggest energy companies in the UK

The three largest UK energy firms by market capitalisation, excluding oil and gas, are:

National Grid (LSE: NG)

National Grid is the UK's largest energy business and is in charge of running the country's power and gas networks. It also provides services in the United States.

It is currently one of the top 20 largest businesses in the United Kingdom by market capitalisation and one of the major global public energy organisations. It was established during the privatisation of the UK energy sector in the 1990s.


SSE is a utility business that services customers in the United Kingdom and Ireland. Its headquarters are in Perth, Scotland, and it was originally known as Scottish and Southern Energy. In 1988, Scottish Hydro-Electric and Southern Electric merged to create the company.

Utilities United (LSE: UU)

United Utilities is the largest openly traded water business in the United Kingdom. It serves North-West England, including Greater Manchester, Cumberland, Merseyside, Lancashire, and portions of Cheshire.

The biggest insurance companies in the UK

The three largest UK insurance firms by market capitalisation are:

Prudential (LSE: PRU)

Prudential is the largest insurance business in the United Kingdom by market capitalisation. It is headquartered in London and primarily serves African and Asian countries, providing life and health insurance as well as asset management. Prudential is listed on the London, Hong Kong, Singapore, and New York stock exchanges.

Aviva (LSE: AV)

Aviva is a British insurance business headquartered in London. Its roots go back to the ‘Hand in Hand Fire and Life Insurance Company’ founded in 1696, which makes it arguably one of the oldest companies on the London Stock Exchange. The current Aviva was established in 2000 when Norwich Union and CGU combined. In 2002, it changed its brand name to Aviva.

Admiral Group (LSE: ADM)

Admiral Group is a global insurance company headquartered in the United Kingdom that controls the Admiral, Diamond, Bell, and Veygo names. It also owned the insurance comparison website confused.com until 2021, when it was sold. Admiral began as a provider of motor vehicle insurance and has since expanded to include holiday, home, and pet insurance.

Final thoughts

The FTSE 100, which measures the success of the country's 100 biggest businesses based on market capitalisation, is the most significant stock index in the United Kingdom. The top ten businesses in the index as of April 2023 were a diverse bunch. They included, among others, Europe's second-biggest bank, two international pharmaceutical behemoths, a global consumer goods company, two mining firms, and a global tobacco giant, which shows the importance of knowing about these companies as a trader. However, please bear in mind that this article is informational and should never be considered investment advice. 

People also asked


You can use a spread betting or CFD account to trade on the biggest companies in the United Kingdom. You can trade on the FTSE 100 index itself, referred to as the ‘UK 100’ or the individual stocks themselves. Learn more about spread betting vs CFDs to understand the distinctions between the two and determine which is best for you.


The United States is home to some of the world's biggest corporations, including tech behemoths Alphabet, Apple, Microsoft, Tesla, and Amazon. But there are other giant corporations around the world, including Saudi Arabia’s Aramco, Taiwan’s TSMC, and China’s Sinopec, Tencent, and Alibaba.


The majority of the largest UK businesses are classified as blue-chip. These are companies that were founded many years ago and had a large customer following as well as a recognised brand value.


The top FTSE 100 companies are AstraZeneca, Shell, Linde, HSBC Holdings, Unilever Group, BP, Diageo, Rio Tinto Group, Glencore, British American Tobacco, and GlaxoSmithKline.

Suggested articles

See allarrow-icon

Gain the edge

Sign up and unlock early
access to exclusive trading
insights and tips.

You're signed up

Best decision you've made all week!

Something isn't right

Let's try that again

I confirm I am 18 years old or above.

By signing up to hear from us, you agree to our terms and privacy policy.

Please keep me updated on Trade Nation’s sponsorships, news, events and offers.

The markets are moving.

Start trading now.

Get startedarrow-icon

Trade on our


Payment methods

Visa card payment method
Mastercard payment method
Nuapay payment method
Skrill payment method
Neteller payment method
Apple pay payment method

Download mobile apps

Regulatory bodies

    UK - FCA

    Australia - ASIC

    Seychelles - FSA

    Bahamas - SCB

    South Africa - FSCA

Customer support

Sponsors of your favourite teams

The legal stuff

© 2019-2024 Trade Nation. All Rights Reserved