What are industry codes?
Industry codes are numerical systems used to classify companies, organizations and traders into groupings based on how they operate.
The most popular classifications used in North America are NAICS and SIC codes. Some publishers may also create their own classification. Please note that not all resources allow searching by industry codes.
NAICS codes
North American Industry Classification System (NAICS)
NAICS is a 2- through 6-digit hierarchical classification system. Each digit in the code is part of a series of progressively narrower categories. The first two digits designate the economic sector, the third digit designates the subsector, the fourth digit designates the industry group, the fifth digit designates the NAICS industry, and the sixth digit designates the national industry.
This standard is used by Federal statistical agencies in classifying business establishments for the purpose of collecting, analyzing, and publishing statistical data related to the U.S. business economy. NAICS is an industry classification system, not a product classification system.
US Census Bureau NAICS Codes & Understanding Industry Classification Systems
SIC codes
Standard Industrial Classification (SIC)
SIC codes are four-digit numerical codes assigned by the U.S. government to business establishments to identify the primary business of the establishment.
US Department of Labor SIC Manual – includes short descriptions and examples of main products or services. SIC search – allows you to quickly identify relevant codes by performing keyword searches.
SIC is gradually being replaced by NAICS but many resources allow searching by both.
Key resources that allow searching by industry code
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Other classification schemes
Global Industry Classification Standard (GICS)
Industry Classification Benchmark (ICB)
North American Product Classification System (NAPCS)
Central Product Classification (CPC)
Harmonized System (HS) used for international trade statistics