Thomas Cook was a renowned presence in the travel industry, with a strong presence on high streets across the UK. Although the company had been arranging travel packages since the 1800s and early 1900s, it gained recognition in the 1970s, 80s, and early 90s primarily as a travel agency.

In 1996, Thomas Cook expanded its reach by acquiring tour operators Time Off and Sunworld. Over the next three years, they further diversified their portfolio by adding tour operators like Inspirations, Sunset, and Flying Colours, along with the acquisition of the airline Caledonian Airways. Thomas Cook consolidated its tour operations under the JMC brand, which bore the initials of James Mason Cook, the son of the company's founder.

Following a sale to a German company in 2001, which led to the formation of Thomas Cook AG, the company merged with the MyTravel Group in 2007, originally known as Airtours, to create the Thomas Cook Group. In the UK, the Thomas Cook Group operated under the brand names of Thomas Cook and Airtours.

Unfortunately, due to various factors, including a reported debt exceeding �1.6 billion, the Thomas Cook Group ceased trading and entered into administration on Monday, September 23, 2019.

In September 2020, Fosun International relaunched the Thomas Cook brand as Thomas Cook Holidays, operating as an online travel agent (OTA), and it continues to operate to this day.