Official NAICS & SIC Code Reference
Look up official NAICS and SIC codes with definitions, scope notes, and crosswalks.
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Official NAICS & SIC Classification Reference · Since 1998
Find the right NAICS or SIC code
Look up official NAICS and SIC codes, understand what they mean, and access verified company data behind each industry. Used for business lists, compliance research, CRM enrichment, market sizing, and analytics.
Search: plumbing contractor
High Confidence
NAICS Match · Primary
238220
Plumbing, Heating, and Air-Conditioning Contractors
View NAICS Details →Total Verified Companies
88,738
Plumbing, Heating & Air-Conditioning Contractors
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Established 1998
Official definitions & crosswalks
Cited in academic & government research
Verified U.S. company data
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What are NAICS and SIC codes?
NAICS, the North American Industry Classification System, and SIC, the Standard Industrial Classification system, are codes used to identify what a business does. They help group companies by industry for business research, marketing, compliance research, lending, contracting, analytics, and data organization.
NAICS is the primary classification system used by U.S. federal statistical agencies, while SIC remains widely used in private-sector business data, marketing lists, financial records, and historical datasets. Many companies are mapped to both systems so users can compare industries, build targeted business lists, enrich CRM records, and analyze markets consistently.
Choosing the right code matters because industry classification affects how a company is found, compared, reported, segmented, and analyzed.
Reviewed by the SICCODE.com Industry Classification Review Team · Updated 2026
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