Answer

The Standard Industrial Classification "SIC" is a classification system that uses a four-digit code for classifying a company's primary industry which is based upon the company’s highest revenue category.  The SIC was established in the United States in the late 1930s and focused on U.S. companies.  The North American Industry Classification System “NAICS” was introduced in 1997.  NAICS codes are used to classify business establishments within the United States as well as Canada and Mexico as well as industries not previously covered by the SIC system. 

To find out how a company is classified, go to the Business Library's Company & Financial Information section for links to useful resources including links to the following suggested resources.

Hoovers: Provides both SIC and NAICS classifications. 

Reference USA: Provides both SIC and NAICS classifications. 

For a list of codes, you may want to visit the following websites:

NAICS - North American Industry Classification System 

SIC - https://classcodes.com/sic-code-list/

SIC - https://www.sec.gov/info/edgar/siccodes.htm for a list of codes or to search for a company in the EDGAR Filings. The company SIC data is listed with the filing data.