What are SIC and NAICS codes ?

Both Standard Industrial Classification (SIC) and North American Industrial Classification System (NAICS) codes identify a firm's primary business activity.

Standard Industrial Classification Codes (SIC Codes) identify the primary line of business of a company. It is the most widely used system by US government, public, and private organizations.

North American Industry Classification System (NAICS Codes) is the alternative code structure, updated every 5 years.

Every registered Washington firm is assigned a SIC or NAICS code. SIC codes can be up to four digits and NAICS codes can be up to six digits. The Quarterly Business Review (QBR) and the other Create a Report functions (i.e. Gross Business Income report, Statewide Taxable Retail Sales report, Local Sales/Use report) use these codes to group firms together to create informative and useful information. Because the national standard changed from the use of SIC codes to the use of NAICS codes, in November 2004 the Department stopped assigning SIC codes and now only assigns NAICS codes.