Business Feasibility Analysis and Plan Writing Resource Guide: NAICS & SIC Codes

The NAICS and SIC codes are the most commonly used industry classification codes in the United States. These codes categorize companies by their business activity. 

By knowing the NAICS and/or SIC code for your company, you will be able to locate information about its industry and competitors in databases, books, and on the Internet.

Some resources will provide you only the company's primary industry code while other sources may also give you secondary codes.  The primary code represents the line of business for which the company makes the most income.

Standard Industrial Classification (SIC) System

• Developed by the U.S. government in the late 1930s and last revised in 1987. 
• While no longer being maintained by the federal government, SIC codes still appear in some databases and reference books as well as in EDGAR filings of the U.S. Securities and Exchange Commission (SEC). 
• Officially, SIC codes contain up to four digits.  The longer the number, the more specific the industry.

North American Industry Classification System (NAICS)

• Developed in 1997 by government agencies of the three NAFTA countries:  U.S., Canada, and Mexico.
• NAICS is pronounced as "nakes," thus rhyming with "snakes." 
• Officially, NAICS codes contain up to six digits.  The longer the number, the more specific the industry.
• For additional information, click on the links below.

Click on the link below to convert:

• A SIC code to a NAICS code.
• A NAICS code to a SIC code.
• A NAICS code from one edition to another edition.

The sources below are places to search for your company's NAICS codes.

It is best to search in the North American Industry Classification System (NAICS) itself.  If you locate a code elsewhere, please check the code in NAICS to see if it truly reflects the industry you are researching.

The sources below are places to search for your company's SIC codes.