NAICS Code for Chemical Manufacturing

What Is NAICS 325 for Chemical Manufacturing?

The NAICS code for chemical manufacturing is 325, designated as a primary subsector within Sector 31–33 (Manufacturing) of the North American Industry Classification System. Developed jointly by the U.S. Economic Classification Policy Committee (led by the U.S. Census Bureau), Statistics Canada, and Mexico’s Instituto Nacional de Estadística y Geografía (INEGI), NAICS provides a common production-oriented framework for classifying economic establishments across North America. To identify how NAICS hierarchy is structured across all manufacturing lines, see our general reference on NAICS code lookup.

Establishments classified under chemical manufacturing NAICS code 325 transform organic and inorganic raw materials through chemical processes to yield chemical products, preparations, and formulations. The system explicitly distinguishes establishments that produce primary basic chemicals from those that process primary outputs into formulated intermediates and consumer-ready goods. The classification system operates on a mandatory five-year revision cycle (1997, 2002, 2007, 2012, 2017, and 2022) to account for emerging chemical technologies, bio-based feedstocks, and industrial restructuring.

Crucially, NAICS classification is establishment-based rather than enterprise-based. An individual facility is categorized under naics code 325 based on its primary physical production activity at that specific site, determined by the activity accounting for the largest share of production value or revenue. Establishments engaged purely in physical extraction without chemical transformation remain in Sector 21 (Mining), while petroleum refineries that produce primary fuels belong to Subsector 324 (Petroleum and Coal Products Manufacturing).

The 7 Core Industry Groups within NAICS 325

The official 2022 NAICS structure defines seven distinct 4-digit industry groups beneath Subsector 325. These groups organize 55 individual 6-digit national industry classifications based on process similarity, chemical transformation pathways, and product characteristics:

NAICS Code	Industry Group Title	Scope and Primary Chemical Outputs	Representative 6-Digit Codes
3251	Basic Chemical Manufacturing	Primary chemical synthesis from hydrocarbons, atmospheric gases, and minerals	325110 (Petrochemical), 325120 (Industrial Gas), 325130 (Synthetic Dye and Pigment), 325180 (Basic Inorganic)
3252	Resin, Synthetic Rubber, and Fibers	Polymerization of synthetic resins, nonvulcanizable elastomers, and synthetic fibers	325211 (Plastics Material and Resin), 325212 (Synthetic Rubber), 325220 (Synthetic Fibers)
3253	Pesticides, Fertilizers, and Ag Chemicals	Formulation of plant nutrients, soil amendments, insecticides, and herbicides	325311 (Nitrogenous Fertilizer), 325312 (Phosphatic Fertilizer), 325320 (Pesticide)
3254	Pharmaceutical and Medicine Manufacturing	Fabrication of therapeutic substances, biologics, and in-vitro diagnostic reagents	325411 (Medicinal and Botanical), 325412 (Pharmaceutical Preparation), 325413 (In-Vitro Diagnostics)
3255	Paint, Coating, and Adhesive Manufacturing	Compounding of pigments, resins, and solvents into surface coatings and bonding agents	325510 (Paint and Coating), 325520 (Adhesives and Sealants)
3256	Soap, Cleaning Compound, and Toilet Goods	Preparation of surfactants, household cleaners, polishes, cosmetics, and personal hygiene goods	325611 (Soap and Other Detergent), 325612 (Polish), 325620 (Toilet Preparation)
3259	Other Chemical Product Manufacturing	Miscellaneous chemical products including printing inks, explosives, and compounds	325910 (Printing Ink), 325920 (Explosives), 325998 (All Other Chemical Preparation)

Within this hierarchy, naics 325 ensures that upstream bulk chemical producers (such as chlor-alkali or ethylene crackers under 3251) are methodologically segregated from downstream formulators (such as paint compounding under 3255 or cleaning product blenders under 3256), allowing researchers and regulators to track mass balance and occupational exposure accurately.

Regulatory and Environmental Compliance: EPA TRI and TSCA

The 6-digit industry classification under naics code chemical manufacturing triggers mandatory federal reporting thresholds across environmental and occupational regulatory programs. Most prominent is the Toxics Release Inventory (TRI) program established under Section 313 of the Emergency Planning and Community Right-to-Know Act (EPCRA).

Originally, EPCRA required industrial reporting based on 4-digit Standard Industrial Classification (SIC) codes (primarily Major Group 28, Chemicals and Allied Products). In 2006, the U.S. Environmental Protection Agency (EPA) published a final rule (71 FR 32464) replacing SIC codes with 6-digit NAICS codes for all TRI reporting forms. Because all manufacturing facilities in Sectors 31–33 are covered under 40 CFR 372.23, any facility classified under NAICS 325 that employs 10 or more full-time equivalent employees and manufactures, processes, or otherwise uses a listed toxic chemical in excess of threshold quantities must submit annual TRI Form R or Form A reports. For detailed compliance mechanics regarding release thresholds and chemical accounting, consult our guide to the Toxics Release Inventory.

Beyond EPCRA, classification under NAICS 325 dictates regulatory posture under the Toxic Substances Control Act (TSCA) Chemical Data Reporting (CDR) rule, requiring manufacturing facilities to submit data on chemical identity, production volumes, and site-specific exposure practices. In laboratory research and pilot-scale chemical operations, facilities must also evaluate regulatory incident thresholds, as detailed in our analysis of OSHA-reportable laboratory injuries.

Federal Grants, Procurement, and Economic Survey Benchmarking

Federal research agencies, procurement offices, and economic statisticians rely on NAICS 325 codes to structure funding programs, solicitations, and aggregate industrial analyses:

• Annual Survey of Manufactures (ASM) Benchmarking: Conducted annually by the U.S. Census Bureau during intercensal years, the annual survey of manufactures provides detailed statistical estimates of employment, total payroll, supplemental labor costs, cost of materials, and total value of shipments across NAICS 325. Within U.S. manufacturing, Subsector 325 consistently ranks third nationwide in total value of shipments (exceeding $800 billion annually), reflecting immense capital expenditure in continuous-flow processing plants.
• Small Business Size Standards (13 CFR 121): In federal grant allocations and procurement (including Small Business Innovation Research / SBIR awards), the Small Business Administration (SBA) establishes small business eligibility thresholds pegged to specific 6-digit NAICS codes under 325. For example, while basic chemical manufacturers (3251) typically have employee size caps between 1,000 and 1,250 employees, certain specialty preparation codes have 500-employee limits. Review our procedural breakdown of 13 CFR 121 size regulations for exact determination methodologies.
• Federal Procurement and Contracting: When federal agencies contract for chemical formulations, solvents, or biological products through SAM.gov, NAICS 325 codes operate alongside Product and Service Codes (PSCs) to define scope of work, technical requirements, and set-aside eligibility. See our primer on PSC code selection to evaluate how procurement identifiers interact with NAICS designations.

Common Classification Boundaries and Errors

Industrial compliance officers and institutional researchers frequently encounter three boundary pitfalls when assigning or interpreting NAICS 325 codes:

• Conflating Petroleum Refining (324110) with Basic Petrochemicals (325110): Petroleum refineries that crack crude oil primarily into motor fuels, lubricating oils, and asphalt belong to NAICS 324 (Petroleum and Coal Products Manufacturing). Establishments that produce acyclic hydrocarbons, ethylene, propylene, and butadiene primarily as chemical intermediates are classified under NAICS 325110.
• 3-Digit Generalization vs. 6-Digit Mandate: Subsector 325 is a summary category. Regulatory filings, including EPA TRI submissions and federal grant profiles in SAM.gov, reject a 3-digit code; they require the exact 6-digit national industry code (such as 325412 for pharmaceutical preparations or 325510 for paint manufacturing).
• Manufacturing vs. Merchant Wholesaling: An establishment that receives bulk chemicals, dilutes or repackages them into drums, and distributes them without chemical synthesis or formulated property alteration may be classified under Wholesale Trade (NAICS 424690, Other Chemical and Allied Products Merchant Wholesalers) rather than chemical manufacturing.

Frequently Asked Questions

What is the difference between NAICS code 325 and SIC code 28?

Standard Industrial Classification (SIC) Major Group 28 was the four-digit classification system used by U.S. federal agencies prior to 1997. NAICS 325 replaced SIC 28 to establish a modern, production-oriented classification across the United States, Canada, and Mexico. While SIC 28 grouped establishments largely by demand and product end-use, NAICS 325 classifies facilities strictly by their underlying chemical transformation and production processes.

How does a multi-product facility determine its primary NAICS 325 code?

Under Census Bureau and OMB guidelines, a plant that produces multiple chemical lines derives its primary NAICS code from the single activity accounting for the largest share of production value or revenue. If secondary activities exceed threshold volumes, facilities may be required to document secondary NAICS codes for state air operating permits or environmental disclosures.

Are independent chemical research laboratories classified under NAICS 325?

Standalone commercial or academic research laboratories conducting physical and chemical research without commercial-scale manufacturing are classified under Sector 54 (Professional, Scientific, and Technical Services), specifically NAICS 541715 (Research and Development in the Physical, Engineering, and Life Sciences). Pilot plants that operate as integrated units within an active chemical manufacturing plant are classified under the corresponding NAICS 325 production code.

Sources

• U.S. Census Bureau, “2-6 digit 2022 NAICS Codes” Classification Table. https://www.census.gov/naics/2022NAICS/2-6%20digit_2022_Codes.xlsx (read 2026-11-07).
• U.S. Environmental Protection Agency (EPA), “Chemical Manufacturing Sector (NAICS 325)”. https://www.epa.gov/regulatory-information-sector/chemical-manufacturing-sector-naics-325 (read 2026-11-07).
• U.S. Environmental Protection Agency (EPA), “TRI-Covered Industry Sectors” under EPCRA Section 313. https://www.epa.gov/toxics-release-inventory-tri-program/tri-covered-industry-sectors (read 2026-11-07).
• U.S. Census Bureau, “2022 NAICS Manual & Annual Survey of Manufactures Overview”. https://www.census.gov/naics/ (read 2026-11-07).