Revenue of Deloitte worldwide by service line 2006-2021

Revenue from all four Deloitte’s service lines has increased year-on-year over the last decade; their largest service line was consulting, which generated around 20.8 billion U.S. dollars of revenue (out of a total revenue of 50.2 billion U.S. dollars) in 2021.

Deloitte’s business units

Deloitte Touche Tohmatsu, generally referred to simply as Deloitte, is a global accounting firm operating in over 150 countries. Headquartered in New York City, the company provides services across a wide variety of industries, with around half their revenue being derived from the financial services and consumer business and transportation sectors. Since 2013, Deloitte has been divided into five service lines: audit and assurance, consulting, financial advisory, risk advisory and tax and legal. Prior to this, audit and assurance and risk advisory were combined.

The Big Four

In terms of total revenue, Deloitte is the largest of the Big Four global accountancy firms. Deloitte’s leading position results from its presence in the American market, which accounts for just over half their revenue. The second largest of the Big Four, PwC, actually holds a higher market share in Europe, the Middle East, Africa and the Asia-Pacific region. PwC also generates the greatest revenue of the Big Four from tax, audit & risk advisory services, whereas Deloitte are the leader for consulting services.