517121 — Telecommunications Resellers
Description
This U.S. industry comprises establishments engaged in purchasing access and network capacity from owners and operators of telecommunications networks and reselling wired and wireless telecommunications services to businesses and households (except satellite telecommunications and agents for wireless telecommunications services). Establishments in this industry resell telecommunications; they do not operate transmission facilities and infrastructure (as defined in the official U.S. Census Bureau 2022 NAICS Manual).
Illustrative Examples
- Mobile virtual network operators (MVNOs) (except agents)
- Pre-paid calling cards, telecommunications resellers
- Wired telecommunications resellers
- Wireless telecommunications resellers (except satellite telecommunications and agents)
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 4812 - Radiotelephone Communications (via SIC1987:4812→NAICS1997:51333→2002:517310→2007:517911→2012:517911→2017:517911→2022:517121)
- SIC 4813 - Telephone Communications, Except Radiotelephone (via SIC1987:4813→NAICS1997:51333→2002:517310→2007:517911→2012:517911→2017:517911→2022:517121)
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 7G21 — Digital network communications hardware, software, and other equipment used within the core data centers and work areas, connecting end users to the organization's Local Area Network (LAN). Wide Area Network (WAN) digital transmission equipment, supporting hardware and software directly connecting data centers, offices and third parties. Includes 1) external digital network transport equipment (Outside Plant) physical communications infrastructure connecting to LAN/WAN end points 2) copper and fiber communications systems, and 3) cellular infrastructure such as towers, repeaters, switching systems dedicated for cellular communication. Products and tools that enable or distribute voice services through on-premise digital equipment including PBX, VoIP, voicemail and handsets.
Source: DoD DPCAP PSC Selection Tool (Ingested: 2026-06-29)
Frequently Asked Questions (FAQ)
Is NAICS code 517121 valid in 2022? ▾
Yes, 517121 is a valid 6-digit 2022 NAICS national industry code representing 'Telecommunications Resellers' under Sector 51 in the official classification index.
What is the SBA size standard for NAICS code 517121? ▾
The Small Business Administration (SBA) has established a small business size standard of 1,500 employees for NAICS code 517121 (Telecommunications Resellers), calculated based on employees.
What is the legacy SIC equivalent for NAICS 517121? ▾
According to official Census Bureau concordance tables, NAICS code 517121 (Telecommunications Resellers) maps to legacy 1987 Standard Industrial Classification (SIC) codes: 4812 - Radiotelephone Communications, 4813 - Telephone Communications, Except Radiotelephone.
Related Pages & Tools
Further regulatory reference links for NAICS code 517121:
- Sector 51 Directory Hub — List of related industries in the Information sector.
- SIC ↔ NAICS Crosswalk Tool — Look up mappings between legacy SIC codes and modern classifications.
- NAICS 517121 to SIC Crosswalk — Bidirectional mapping to legacy SIC codes (Telecommunications Resellers).
- 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.