SIC 4492 to NAICS Code Crosswalk
The legacy 1987 SIC code 4492 (Towing and Tugboat Services) maps transitively to modern U.S. Census 2022 NAICS code(s): 488330.
Concordance Concordance Mapping Asset
| Source Code | Source Industry | Target Code | Target Industry | Relation | Concordance Path |
|---|---|---|---|---|---|
| SIC 4492 | Towing and Tugboat Services | NAICS 488330 | Navigational Services to Shipping | 1:1 | SIC1987:4492 → NAICS1997:48833 → 2002:488330 → 2007:488330 → 2012:488330 → 2017:488330 → 2022:488330 |
Why Concordances Don't Line Up 1:1
The Standard Industrial Classification (SIC) system was established in 1937 and last updated in 1987, organizing businesses by end products. The North American Industry Classification System (NAICS) replaced it in 1997, classifying establishments by production processes. Because of this structural shift, many-to-many relationships are common, requiring chained concordance steps to bridge the historical gap.
Reverse Crosswalk: Going the other way? See the mapping at NAICS 488330 to SIC.
Related Pages & Tools
- SIC Code 4492 Profile — Legacy OSHA definition and associated industrial metadata.
- SIC Major Group 44 Hub — Legacy category group directory.
- Interactive Crosswalk Engine — Convert any SIC or NAICS code dynamically.
Primary Ingestion Source
Data sourced from the U.S. Census Bureau Concordances (1997, 2002, 2007, 2012, 2017, and 2022 editions). Last verified on 2026-06-30.