The U.S. government created the Standard Industrial Classification (SIC) system in 1937 to classify business establishments by type of economic activity. Beginning in 1997, the U.S., Canada, and Mexico switched to a new system called the North American Industrial Classification System or NAICS. Besides federal, state, and local governments, commercial publishers make industry data available organized by NAICS. You'll often need to know the code for your industry when doing research in order to find relevant information. You can use the links below to find the number you need.
Search for a NAICS code.
Search for an SIC code.
If you know either the NAICS or SIC and need the corresponding code, please use the link below.
Correspondence tables that show the correlation between NAICS and SIC numbers.