What Is a SIC Code, Who Needs a SIC Code, and How To Find Yours

What Is a Standard Industrial Classification (SIC) Code?

Standard Industrial Classification (SIC) codes are four-digit numerical codes assigned by the U.S. government that categorize the industries to which companies belong, while also organizing industries by their business activities. The SIC codes were created by the U.S. government in 1937 to classify and analyze economic activity across various industries and government agencies, and to promote uniformity in the presentation of statistical data collected by various government agencies SIC codes have also been adopted in places outside the U.S., including in the U.K.

Key Takeaways

  • Standard Industrial Classification (SIC) codes are four-digit numerical codes that categorize the industries that companies belong to based on their business activities.
  • Standard Industrial Classification codes were mostly replaced by the six-digit North American Industry Classification System (NAICS).
  • Despite having been replaced, government agencies, including the SEC, and some companies still use SIC codes today.
  • The first two digits represent the highest level business classification, while the subsequent two digits are used to further refine the identification.
  • The government uses SIC codes to property assign the review of financial filings to the appropriate divisions to ensure all requirements are met.

However, Standard Industrial Classification codes were mostly replaced in 1997 by a system of six-digit codes called the North American Industry Classification System (NAICS). The NAICS codes were adopted in part to standardize industry data collection and analysis between Canada, the United States, and Mexico, which had entered into the North American Free Trade Agreement.

Despite having been replaced, government agencies and companies still use the SIC standardized codes today for classifying the industry that companies belong to by matching their business activity with like companies.

Understanding Standard Industrial Classification (SIC) Codes

The SIC system classifies the economy into 11 major divisions:

  • Agriculture, forestry, and fishing
  • Mining
  • Construction
  • Manufacturing
  • Transportation and public utilities
  • Wholesale trade
  • Retail trade
  • Finance, insurance, real estate
  • Services
  • Public administration
  • Nonclassifiable establishments

These are then divided into 83 two-digit major groups, and further subdivided into 416 three-digit industry groups and then into more than 1,000 four-digit industries.

Every company has a primary SIC code that indicates its main line of business. The first two digits of the SIC code identify the major industry group, the third digit identifies the industry group, and the fourth digit identifies the specific industry.

The Securities and Exchange Commission (SEC) is a major government agency that regulates the markets. The SEC still uses SIC codes. The SIC codes are listed in a company's electronic data gathering, analysis, and retrieval system filings (called EDGAR) to indicate the company's industry.

SIC Codes vs. NAICS codes

The SIC code system continues to remain the most popular industry classification system. The NAICS code system has been unable to fully replace it due to the SIC system's long history, and the reluctance of businesses and other organizations that have been long-term users of SIC codes to switch over to a new classification system.

Although the U.S. government stopped updating SIC codes as far back as 1987, private data organizations stepped in and continued to update the SIC system, including adding very specific additional classifications. As a result, at the most defined levels, there are currently over 10,000 six-digit SIC codes (compared with 1,066 NAICS codes).

With the increased degree of integration within the North American economy following the establishment of NAFTA, U.S. companies now have both a SIC code and a NAICS code.

How SIC Codes are Used

Businesses and the government use SIC codes in a number of ways, as discussed below.


  • Companies use SIC codes to identify their existing customers and potential customers by industry.
  • SIC codes can be used to classify companies for tax purposes.
  • Banks and creditors use SIC codes to identify the industry a company belongs to when considered extending credit. 
  • SIC codes are used by professionals and businesses to create targeted marketing campaigns.
  • Companies can identify the competition in their industry or region by searching for like companies via SIC codes.
  • Businesses also use SIC codes to identify government contracts.


  • The government uses SIC codes to organize and standardize key economic data for various Federal and state agencies as well as private companies.
  • SIC codes make it easier to compare data across disparate government agencies.
  • SIC codes are also used for tax classification.
  • The SEC uses SIC codes when sorting company filings.

How to Find Your SIC Code

There are many different ways to find the most appropriate SIC code for a company. Examples of various usable resources include:

  • The United States Department or Labor maintains an online system search tool to search SIC codes by keywords.
  • If you know your NAICS code, there are online resources to identify corresponding SIC codes.
  • The Security and Exchange Commission publishes the report via PDF.

How to Read SIC Codes

Each digit within a SIC code has a meaning; to read a SIC code, each set of digits should be independently evaluated to determine the overall meaning of the code.

The First Two Digits

The first two numbers of a SIC code identifies the business's major sector group. Though the number of major groups fluctuates, there are typically less than 100 major groups. These major groups all fit into one of the 11 major divisions, and these first two digits define what industry the company is in.

The Third Digit

The third digit is the second independent feature that describes a company. This third digit further refines the business classification and is often referred to as the business industry group. For example, if code 23xx refers to apparel companies:

  • 232x identifies men's and boy's furnishings.
  • 233x identifies women's and misses' furnishings.

The Fourth Digit

The last digit of a SIC code is the most specific identifier of a company. Factoring in this last digit, there are now over 1,000 combinations. For example, SIC code 2050 (emphasis on the final digit) represents bakery products, while SIC code 2052 represents cookie & cracker manufacturers. This fourth digit further refines the business classification into a very specific business category.

Real-World Examples of SIC Codes

Apple Inc.'s SEC filings show its SIC code as 3571 (electronic computers). The first two digits—35—identify its major industry group as "Industrial and Commercial Machinery and Computer Equipment," while the third digit—7—narrows its industry group down to "Computer and Office Equipment" and the final digit—1—classifies it as "electronic computers." Note that if the first two digits are between 20 and 39, these companies are classified in the manufacturing division or segment of the economy.

Despite the SIC codes having been replaced by NAICS, you can still search for them. Below is an image of the Standard Industrial Codes, along with their meaning, for the banking industry (taken from the SEC's website).

  • Bank of America Corporation (BAC), for example, would have the SIC code of 6021 because it's a national commercial bank.
  • State banks would have the SIC code of 6022.
  • Life insurance companies would be classified as 6311.
Standard Industrial Classification (SIC) codes from the Securities and Exchange Commission
Examples of Standard Industrial Classification (SIC) codes from the Securities and Exchange Commission.  Investopedia

How Do I Find My Company's SIC Code?

The United States Securities and Exchange Commission publicly issues a standard code list that can be used to identify a SIC code. The code list is more specifically reviewed and updated by the Division of Corporation Finance.

Who Needs a SIC Code?

All companies naturally have a SIC code, as there are over 1,000 total SIC codes possible. Companies that file public reports are often required to use SIC codes when reporting, as the SEC uses it as a basis for assigning review responsibility for company filing requirements.

What Is an Example of a SIC Code?

SIC code 6500 represents the entire real estate industry. SIC code 6510 identifies real estate operators, while SIC code 6512 further refines the classification to nonresidential buildings while 6513 further refines the classification to operators of apartment buildings.

What Does SIC Code Stand for?

SIC code stands for standard industrial classification (SIC) code This four digit-number identifies a very specific short descriptor of the type of business a company is engaged in.

The Bottom Line

To help identify the appropriate reviewer of company filings based on the industry a company operates within, the Securities and Exchange Commission publishes a listing of standard industrial classification (SIC) codes. When issuing reports, companies must report the SIC code that most closely identifies with their operations.

Article Sources
Investopedia requires writers to use primary sources to support their work. These include white papers, government data, original reporting, and interviews with industry experts. We also reference original research from other reputable publishers where appropriate. You can learn more about the standards we follow in producing accurate, unbiased content in our editorial policy.
  1. Office of Statistical Standards. "History of the Standard Industrial Classification," Page 1.

  2. U.K. Government. "Standard Industrial Classification of Economic Activities (SIC)."

  3. Census Bureau. "North American Industry Classification System."

  4. U.S. Securities and Exchange Commission. "Division of Corporation Finance: Standard Industrial Classification (SIC) Code List."

  5. United States Department of Labor. "Standard Industrial Classification (SIC) System Search."

  6. NAICS Association. "NAICS & SIC Crosswalks."