NAICS codes – North American Industry Classification System (NAICS)
The North American Industry Classification System (NAICS) is the official industry classification system used by federal statistical agencies to collect, analyze, and publish data about the U.S. economy. In the United States, NAICS is maintained by the U.S. Census Bureau and provides a standardized framework for classifying business establishments based on primary economic activity. See the Census Bureau’s NAICS overview and definitions.
What Is NAICS?
NAICS provides a consistent way to classify businesses for statistical reporting. It is used across North America and replaced the former Standard Industrial Classification (SIC) system to better reflect the modern economy. The Census Bureau explains how NAICS is used and structured in its official NAICS resources.
How NAICS Codes Work
A NAICS code is a six-digit numeric identifier. Each additional digit narrows the classification:
- First two digits: Sector
- Third digit: Subsector
- Fourth digit: Industry group
- Fifth digit: Industry
- Sixth digit: National industry
For additional background on how the system is used in federal statistics, the Census Bureau provides guidance on understanding NAICS.
Why NAICS Codes Are Important
Economic Data and Federal Statistics
NAICS is used in federal statistical programs to standardize industry reporting and enable consistent comparisons over time. The Census Bureau’s NAICS guidance explains how NAICS supports U.S. economic measurement.
Government Contracting and Compliance
In U.S. federal contracting, solicitations are assigned a NAICS code, and that NAICS code is used to determine the applicable small business size standard. The SBA outlines requirements for businesses seeking federal contracts in its basic federal contracting requirements and explains the relationship to size standards in its Size Standards guidance.
NAICS Sectors and Descriptions
NAICS organizes economic activity into 20 broad sectors. Each sector is identified by the first two digits of a NAICS code. You can look up any sector using the Census Bureau’s official NAICS lookup page.
| Sector | Description |
|---|---|
| 11 – Agriculture, Forestry, Fishing and Hunting | Establishments primarily engaged in growing crops, raising animals, harvesting timber, and harvesting fish and wildlife. |
| 21 – Mining, Quarrying, and Oil and Gas Extraction | Establishments that extract naturally occurring mineral solids, liquids, or gases. |
| 22 – Utilities | Establishments that provide electric power, natural gas, water supply, steam supply, and sewage removal. |
| 23 – Construction | Establishments engaged in the construction of buildings, engineering projects, and specialty trade activities. |
| 31–33 – Manufacturing | Establishments engaged in the mechanical, physical, or chemical transformation of materials into new products. |
| 42 – Wholesale Trade | Establishments engaged in wholesaling merchandise for resale or business use. |
| 44–45 – Retail Trade | Establishments primarily engaged in retailing merchandise directly to consumers. |
| 48–49 – Transportation and Warehousing | Establishments providing transportation of passengers or cargo, warehousing, and storage services. |
| 51 – Information | Establishments engaged in producing and distributing information and cultural products. |
| 52 – Finance and Insurance | Establishments engaged in financial transactions, insurance underwriting, and related activities. |
| 53 – Real Estate and Rental and Leasing | Establishments involved in real estate, rental, and leasing activities. |
| 54 – Professional, Scientific, and Technical Services | Establishments providing professional, scientific, and technical services, including legal and accounting services. |
| 55 – Management of Companies and Enterprises | Establishments that hold equity interests in other companies or manage and administer them. |
| 56 – Administrative and Support and Waste Management and Remediation Services | Establishments providing administrative support, waste management, and remediation services. |
| 61 – Educational Services | Establishments that provide instruction and educational training. |
| 62 – Health Care and Social Assistance | Establishments providing health care and social assistance services. |
| 71 – Arts, Entertainment, and Recreation | Establishments engaged in arts, entertainment, and recreational activities. |
| 72 – Accommodation and Food Services | Establishments providing lodging and food services. |
| 81 – Other Services (except Public Administration) | Establishments providing services not classified elsewhere. |
| 92 – Public Administration | Government establishments engaged in public administration. |
How to Find the Correct NAICS Code
You can identify the appropriate NAICS code by using the Census Bureau’s NAICS lookup and search tools.
For federal contracting, businesses typically list NAICS codes during registration and contracting preparation; the SBA summarizes these steps in its basic requirements for federal contracting.
NAICS Codes and Small Business Size Standards
NAICS codes are used by the SBA to determine which small business size standard applies to a contract or program.
Official size standards are published in the SBA’s Table of Size Standards, and the SBA provides additional guidance in its Size Standards page.
NAICS Updates and Revisions
NAICS is updated periodically to reflect changes in the economy and industry structure. The Census Bureau provides current NAICS materials and reference files through its official NAICS page.
Conclusion
NAICS is the official federal standard for classifying business establishments by industry in the United States.
Correctly identifying your NAICS code supports accurate reporting, government contracting alignment, and consistent industry classification across federal data systems.
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