There are two places named Big Four in the United States.
- Big Four in Snohomish County, Washington
- Big Four in McDowell County, West Virginia
- Big 4 accountancy firm.
- a nickname for a railroad in the United States of America officially called the Cleveland, Cincinnati, Chicago and St. Louis (later absorbed by the New York Central Railroad).
- name given to the four biggest banking companies in the United Kingdom, these are Lloyds TSB, the Royal Bank of Scotland, Barclays Bank and HSBC.
- name given to the four large banks in the People's Republic of China, these are the Bank of China, the China Construction Bank, the Industrial and Commercial Bank of China and the Agricultural Bank of China.
- collective name given to four railroad magnates in the western U.S.: Collis P. Huntington, Leland Stanford, Mark Hopkins and Charles Crocker