Big business involves large-scale corporate-controlled financial or business activities. As a term, it describes activities that run from "huge transactions" to the more general "doing big things". In corporate jargon, the concept is commonly known as enterprise, or activities involving enterprise customers.

The concept first rose in a symbolic sense after 1880 in connection with the combination movement that began in American business at that time. United States corporations that fall into the category of "big business" as of 2015 include ExxonMobil, Walmart, Google, Microsoft, Apple, General Electric, General Motors, Citigroup, Goldman Sachs, and JPMorgan Chase. The largest German corporations as of 2012 included Daimler AG, Deutsche Telekom, Siemens, and Deutsche Bank. Among the largest companies in the United Kingdom as of 2012 are HSBC, Barclays, WPP plc, and BP. The latter half of the 19th century saw more technological advances and corporate growth in additional sectors, such as petroleum, machinery, chemicals, and electrical equipment. (See Second Industrial Revolution.)