221121 — Electric Bulk Power Transmission and Control
Description
This U.S. industry comprises establishments primarily engaged in operating electric power transmission systems and/or controlling (i.e., regulating voltages) the transmission of electricity from the generating source to distribution centers or other electric utilities. The transmission system includes lines and transformer stations (as defined in the official U.S. Census Bureau 2022 NAICS Manual).
Exclusions & Cross-References
- Generating electric energy--are classified in Industry 22111, Electric Power Generation; and
- Distributing electricity to final consumers--are classified in U.S. Industry 221122, Electric Power
- Distribution.
Overview Facts
Legacy SIC Concordance
Trace the historical mapping chain from the 1987 Standard Industrial Classification (SIC) to the modern 2022 NAICS code format.
- SIC 4911 - Electric Services (via SIC1987:4911→NAICS1997:221121→2002:221121→2007:221121→2012:221121→2017:221121→2022:221121)
- SIC 4931 - Electric and Other Services Combined (via SIC1987:4931→NAICS1997:221121→2002:221121→2007:221121→2012:221121→2017:221121→2022:221121)
- SIC 4939 - Combination Utilities, NEC (via SIC1987:4939→NAICS1997:221121→2002:221121→2007:221121→2012:221121→2017:221121→2022:221121)
Suggested Product Service Codes (Advisory)
The following Product Service Codes (PSCs) are advisory suggestions aligned with this NAICS code. Note: NAICS and PSC codes map to different dimensions of procurement (industry vs. product/service). There is no official binding 1:1 crosswalk.
- PSC M1MZ — OPERATION OF EPG FACILITIES - OTHER, INCLUDING TRANSMISSION
Source: DoD DPCAP PSC Selection Tool (Ingested: 2026-06-29)
Frequently Asked Questions (FAQ)
Is NAICS code 221121 valid in 2022? ▾
Yes, 221121 is a valid 6-digit 2022 NAICS national industry code representing 'Electric Bulk Power Transmission and Control' under Sector 22 in the official classification index.
What is the SBA size standard for NAICS code 221121? ▾
The Small Business Administration (SBA) has established a small business size standard of 950 employees for NAICS code 221121 (Electric Bulk Power Transmission and Control), calculated based on employees.
What is the legacy SIC equivalent for NAICS 221121? ▾
According to official Census Bureau concordance tables, NAICS code 221121 (Electric Bulk Power Transmission and Control) maps to legacy 1987 Standard Industrial Classification (SIC) codes: 4911 - Electric Services, 4931 - Electric and Other Services Combined, 4939 - Combination Utilities, NEC.
Related Pages & Tools
Further regulatory reference links for NAICS code 221121:
- Sector 22 Directory Hub — List of related industries in the Utilities sector.
- SIC ↔ NAICS Crosswalk Tool — Look up mappings between legacy SIC codes and modern classifications.
- NAICS 221121 to SIC Crosswalk — Bidirectional mapping to legacy SIC codes (Electric Bulk Power Transmission and Control).
- SBA Size Standards Guide — Complete rules and averaging periods for small business classifications.
- Calculating Annual Receipts Guide — Detailed worked example of revenue calculation rules.
- IRS Principal Business Activity Guide — How NAICS codes map to corporate and entity tax filings.