Top 10 Biggest UK Companies by Market Cap

The most important stock index in the U.K. is the FTSE 100, which tracks the performance of the 100 largest companies in the country based on market capitalisation. The index, which is pronounced commonly as the "Footsie 100," was created in January 1984. At that time, its baseline value was established at 1,000 points, although stock prices were calculated retroactively back to 1969.^[1]

In this article, we cover the 10 largest publicly traded companies in the U.K. by market capitalisation as of 21 March 2022 in U.S. dollars.^[2]

Market cap is calculated by multiplying the number of the company's common shares outstanding by the market value of each share.

1. AstraZeneca

AstraZeneca is the largest U.K. company by market cap at US$196.37 billion, which also makes it one of the largest pharmaceutical companies in the world.^[2] It was known as Zeneca Group PLC until April 1999 when its name was changed to AstraZeneca PLC.

AstraZenaca's main areas of specialisation include oncology, respiratory and cardiovascular health, and neuroscience.^[3] Among its most well-known consumer products are Prilosec and Nexium for gastroenterology diseases. The company is based in Cambridge.^[3]

2. Linde

Linde, a leading industrial gas and engineering company, is the second-largest publicly-traded U.K. company with a market cap of US$158.41 billion.^[4]

Founded in 1879 and based in Guildford, U.K., Linde processes and sells various types of gases internationally, including natural gas, oxygen, nitrogen, and carbon dioxide. It also serves a variety of industries, including healthcare, petroleum refining, and manufacturing.^[5]

3. HSBC

HSBC Holdings is the third-largest company in the U.K. based on market cap, at US$138.98 billion as of 21 March 2022.^[2] It's the ninth-largest bank in the world in terms of assets, at nearly US$3.0 trillion, and it was the second largest bank based in Europe as of 31 December 2020.^[6]

Despite being based in London, the bank has always been focused on Asia since its founding in 1865. In fact, its original name was Hongkong and Shanghai Banking Corp. Today the company serves 40 million customers in 64 countries and territories.^[7]

4. Rio Tinto Group

Rio Tinto Group is a large international mining and mineral processing company and the fourth-largest U.K. company by market cap, at US$126.63 billion.^[2]

Based in London, the company gets its name from the Rio Tinto River in Andalusia, Spain, where it was founded in 1873. It boasts 49,000 employees in 35 countries, and it produces iron ore, aluminum, copper, diamonds and titanium.^[8]

5. Unilever Group

Unilever is a large London-based consumer products conglomerate. Incorporated in 1894, its brand lineup includes more than 400 different personal and household products, including Vaseline, Dove, Ben & Jerry's, Lipton, Pond's and Sunlight.^[9] The company ranks fifth in terms of market cap at $116.73 billion.^[2]

6. Diageo

Diageo, the sixth-largest U.K. company by market cap at US$114.95 billion, is a large international spirits company.^[2] It makes more than 200 different brands of liquor and beer that it markets in more than 180 countries globally.^[10]

Among its best known products are Johnnie Walker, Smirnoff, Baileys, Captain Morgan, Tanqueray and Guinness. The company was founded in 1886 and is based in London.^[11]

7. GlaxoSmithKline

GlaxoSmithKline (GSK) is a large pharmaceutical conglomerate that dates back to 1715 from its founding as a London apothecary shop. Today it employs about 100,000 people around the world.^[12] GSK is the seventh-largest company in the U.K. by market cap, at US$110.40 billion.^[2]

In the consumer realm, the company focuses on oral health, nutrition and skin health. Among its most familiar brand name products are Sensodyne, Poligrip, and Theraflu. GSK is based in Brentford.^[13]

8. British American Tobacco

London-based British American Tobacco (BAT) is the eighth-largest U.K. company, valued at US$98.0 billion as of 21 March 2022.^[2]

Founded in 1902, the company makes cigarettes, cigars, oral tobacco and nicotine products, as well as vapour and tobacco-heating products and e-cigarettes. Its signature brands include Dunhill, Kent, Lucky Strike, Pall Mall, Newport, and Camel.^[14] The company employs more than 53,000 people worldwide and sells its products in more than 180 markets.^[15]

9. BP

BP is a large international energy company and the ninth-largest U.K. company by market cap at US$97.66 billion.^[2] The company was founded in 1889 and is based in London.^[16] The company does business in 79 countries around the world and employs more than 70,000 people.^[17]

10. Anglo American

Anglo American is a large international mining company, specializing in diamonds, copper, platinum, coal, and iron ore. The company has roughly 69,000 employees,^[18] and it was founded in 1917 and based in London.^[19] As of 21 March 2022, it had a market cap of US$70.04 billion.^[2]

Summary

The most important stock index in the U.K. is the FTSE 100, which tracks the performance of the 100 largest companies in the country based on market capitalisation. The top 10 companies in the index as of March 2022 were well diversified, including Europe's second largest bank, two multinational pharmaceutical giants, a global consumer products company, and two mining firms, among others.