Standard Industrial Classification

The Standard Industrial Classification SIC is a system for classifying industries by a four-digit code. Established in the United States in 1937, it is used by government agencies to classify industry areas. The SIC system is also used by agencies in other countries, e.g., by the United Kingdom's Companies House.

In the United States the SIC code is being supplanted by the six-digit North American Industry Classification System (NAICS code), which was released in 1997; however certain government departments and agencies, such as the U.S. Securities and Exchange Commission (SEC), still use the SIC codes.

The SIC codes can be grouped into progressively broader industry classifications: industry group, major group, and division. The first 3 digits of the SIC code indicate the industry group, and the first two digits indicate the major group. Each division encompasses a range of SIC codes:

To look at a particular example of the hierarchy, SIC code 2024 (ice cream and frozen desserts) belongs to industry group 202 (dairy products), which is part of major group 20 (food and kindred products), which belongs to the division of manufacturing.

In the early 1900s, each branch of a United States government agency would conduct business analysis using its own methods and metrics, unknown and meaningless to other branches. In the 1930s, the government needed standardized and meaningful ways in which to measure, analyze and share data across its various agencies. Thus, the Standard Industrial Classification system was born. SIC codes are four-digit numerical representations of major businesses and industries. SIC codes are assigned based on common characteristics shared in the products, services, production and delivery system of a business.

SIC codes have a hierarchical, top-down structure that begins with general characteristics and narrows down to the specifics. The first two digits of the code represent the major industry sector to which a business belongs. The third and fourth digits describe the sub-classification of the business group and specialization, respectively. For example, "36" refers to a business that deals in "Electronic and Other Equipment." Adding "7" as a third digit to get "367" indicates that the business operates in "Electronic, Component and Accessories." The fourth digit distinguishes the specific industry sector, so a code of "3672" indicates that the business is concerned with "Printed Circuit Boards."

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