The Big Four

The Big Four refers to the four largest professional services firms in the world—Deloitte, PricewaterhouseCoopers (PwC), Ernst & Young (EY), and KPMG. These firms provide audit, assurance, tax, consulting, and advisory services to large corporations, governments, and institutions globally. The Big Four play a dominant role in accounting and consulting, often auditing the financial statements of the largest public companies.

Example

A Fortune 500 company hires PwC, one of the Big Four, to conduct its annual financial audit and ensure compliance with international accounting standards.