Electrical Contractors and Other Wiring Installation Contractors (NAICS 238210)

A Histometrics industry primer for public-market and private investors

1. Overview

Electrical contractors are the firms that install and service the wiring, power distribution, lighting, controls, and low-voltage systems inside and around buildings and other structures. When a data center, hospital, factory, apartment complex, or single-family home needs power pulled to it and distributed safely, an electrical contractor does that work — parts and labor, new installs, retrofits, and ongoing service. NAICS (the North American Industry Classification System, the U.S. government's standard framework for classifying businesses) code 238210 is the federal label for this trade. [4]

This is a large, fragmented, labor-intensive service industry that sits directly in the path of three of the biggest capital-spending waves in the economy — the data-center/AI buildout, electrification (electric vehicles, heat pumps, all-electric buildings), and factory reshoring. U.S. electricity demand is rising for the first time in a generation, and almost none of the new load gets used without an electrical contractor connecting it. [7][8][9]

There are two ways in. Public-market investors can buy shares of a handful of large listed contractors and diversified infrastructure firms (Section 4). Private investors — the more natural fit for most of this industry — can own or operate a local contractor, back a private-equity roll-up, provide private credit against backlog and receivables, or finance an ownership transition, because the industry is overwhelmingly made up of thousands of small, privately held, often owner-operated businesses (Sections 3, 4, 10).

Editorial view. The long-term demand setup is the strongest in a generation, but returns still depend heavily on labor availability, estimating discipline, project execution, cash collection, and how much of the work is fixed-price.

2. What it is and how it's structured

Scope. NAICS 238210 covers establishments primarily engaged in installing and servicing electrical wiring and equipment. That includes building power and lighting; airport runway and highway/traffic lighting; fiber-optic and premises/network cabling (inside the building, not long-haul transmission line); fire-alarm and security-alarm systems; home-automation and audio installation; cable-TV hookups; and increasingly solar-panel, battery-storage, and electric-vehicle-charging installation. [4]

The value chain. Work usually flows from a building owner, developer, utility, or government agency to a general contractor, and then to an electrical subcontractor. Larger electrical contractors may also provide design assistance, procurement, prefabrication, installation, testing and commissioning, maintenance, and emergency restoration.

What it excludes (and the adjacent codes). The industry is defined as much by what it leaves out. Read this carefully — it explains why several of the biggest "electrical" companies below are only partly in 238210:

• 237130 — Power and Communication Line and Related Structures Construction: the utility poles, overhead/underground transmission and distribution lines, and substations that move power between the grid and a building. This is the single most important boundary, because several large listed "electrical" firms earn much of their revenue here. [4]
• 238220 — Plumbing, Heating, and Air-Conditioning Contractors: the mechanical (HVAC — heating, ventilation, and air conditioning) and piping trades that often sit next to electrical on a job site.
• 238290 — Other Building Equipment Contractors: elevators and other specialized building equipment.
• 2211 — Electric Power Generation, Transmission and Distribution: the utilities themselves (generating and operating the grid), not the contractors who wire buildings.
• 517 — Telecommunications: carriers installing and maintaining their own transmission lines.
• 561621 — Security Systems Services: alarm sales, monitoring, and maintenance when bundled with monitoring rather than pure installation.
• 441330 — automotive parts/accessories retail: retailing and installing automotive audio equipment. [4]

Ownership mix. This is a fragmented, private, local/regional business. There are roughly 78,975 firms operating about 83,342 establishments — meaning most firms run a single location. [1][2] The mix runs from local owner-operators and family businesses to employee-owned companies (ESOPs — employee stock ownership plans), private-equity-backed platforms, and a few public consolidators. A subset are unionized shops affiliated with the International Brotherhood of Electrical Workers (IBEW) and the National Electrical Contractors Association (NECA); the rest are "merit" (non-union/open) shops. The federal data measure revenue held by firms, not who owns them, so there is no official ownership-by-category split. Only a handful of firms are publicly traded.

3. How big it is

Ground-truth U.S. federal statistics for NAICS 238210 (dollar figures converted from thousands):

Average receipts per firm are about $3.2 million ($249.2 billion ÷ 78,975 firms), and the median operator is far smaller. The $19.0 million figure from the Small Business Administration (SBA) is a federal-contracting eligibility threshold, not an estimate of typical company size. [3]

How concentrated? Barely at all. The four largest firms hold just 4.8% of industry receipts (the four-firm concentration ratio, CR4); the top 8 hold 7.8%, the top 20 hold 12.6%, and even the top 50 firms combined hold only 19.1%. [2] The Herfindahl-Hirschman Index (HHI — a standard concentration gauge where 10,000 is a pure monopoly and anything under 1,500 is "unconcentrated") is just 11.6. [2] In plain terms, this is one of the most fragmented industries in the U.S. economy. No firm has anything close to national pricing power; competition is fought locally, job by job.

The undercount caveat. These figures count employer businesses only — firms with payroll. This trade has a very large tail of self-employed, owner-operator electricians and tiny outfits with no employees on payroll. The Census Bureau publishes these separately as "nonemployer" businesses, and our ground-truth file does not include that count, so we won't put a number on it. [1][2][22] The practical effect: the true number of operating electrical businesses is meaningfully higher than the ~79,000 employer firms shown, even though those micro-operators add relatively little to the revenue and payroll totals. The federal data capture the economic weight of the industry well but undercount the sheer number of small operators. (Note also that government-owned utility operations and in-house public crews are generally classified outside 238210; private contractors doing electrical work on public projects are included.)

Labor context. The U.S. Bureau of Labor Statistics (BLS) counts about 818,700 electricians employed across the whole economy (2024), with a median wage near $62,000, projected 9% job growth through 2034 (faster than the average occupation), and roughly 81,000 openings per year on average. [5] The ~1.0 million industry employees above include helpers, apprentices, estimators, and office staff on top of licensed electricians.

4. The investable universe

Because the industry is so fragmented, there are few pure public plays, and the biggest listed "electrical" names are actually diversified. Read the notes column carefully: only part of each company's revenue is pure 238210-type wiring/installation work — several earn a lot in utility-line construction (237130) or mechanical/HVAC trades (238220).

Public companies

There is no pure electrical-contracting ETF (exchange-traded fund). Diversified investors get exposure through broad U.S. infrastructure/construction funds — for example the Global X U.S. Infrastructure Development ETF (ticker PAVE), which holds Quanta, MasTec, EMCOR and peers alongside equipment makers.

Major private owners and operators

The bigger universe is private. The largest firm in the trade press's national ranking that is not a diversified public giant is Rosendin (100% employee-owned via an ESOP; roughly $3.7 billion in 2024 sales), followed by names such as:

Other significant privately held or regional names in the EC&M national ranking include M.C. Dean, Helix Electric, Guarantee Electrical, and Fisk Electric. [6] The top 50 electrical contractors together posted a record $59.5 billion in 2024 revenue, up 15% year over year — but that is still only about a quarter of the total industry, underscoring how much sits in thousands of smaller shops. [6]

Two once-independent giants illustrate the private-to-public pipeline: Cupertino Electric was acquired by Quanta in 2024 for approximately $1.54 billion, and Miller Electric was acquired by EMCOR in 2025 for approximately $876.8 million. [20][21]

5. How the money works

An electrical contractor makes money on the spread between what it bills and what it costs to put labor and materials in place — and the whole game is estimating, labor productivity, and mix. Materials such as copper, aluminum, steel, switchgear, lighting, controls, and cable may be supplied and marked up by the contractor or bought directly by the customer.

Unit economics. Specialty electrical subcontractors typically run gross margins of roughly 26–34% on project work, but net profit margins are thin — often 5–10%, and 2.5–6% at smaller shops. [15] The gap between gross and net is overhead: trucks, tools, insurance, bonding, estimators, and office staff.

Contract types (who bears the cost risk):

• Fixed-price (lump-sum): the contractor delivers defined work for a set price and bears most of the overrun risk. A bid struck at 28% gross margin can close at 19% or less if labor, materials, or scope move against it. [15]
• Unit-price: paid a fixed rate per installed unit; final revenue depends on quantities.
• Time-and-materials: the customer pays negotiated labor rates and reimburses materials.
• Cost-plus: the customer reimburses allowable costs plus a fee, sometimes under a ceiling.

Fixed-price work can produce attractive margins when estimates are accurate, but a labor shortage, design change, material spike, weather delay, or productivity problem can erase the profit. Because revenue is generally recognized as work is performed (measured against estimated total cost), earnings are sensitive to changes in estimates, not just cash collected — public filings stress tracking change orders and revising expected project margins as work progresses. [18]

The metrics owners and investors watch:

• Backlog and book-to-bill. Signed-but-not-yet-built work (remaining performance obligations), and new awards relative to revenue. A rising backlog and a book-to-bill above 1.0 signal future growth; it is the single most-watched number for the public names.
• Labor productivity / billable field hours. Labor is the largest and riskiest cost; revenue per field hour and utilization drive profitability more than anything else.
• Service-vs-project mix. Recurring service and maintenance work carries the highest margins (~45–55% gross), and the most profitable contractors derive 25–40% of revenue from it. [15] Project work is lumpier and lower-margin.
• Change orders and "margin fade." Extra work added mid-project; top estimators capture points of margin that weaker ones leave behind, while fade on jobs nearing completion is a warning sign. [15]
• Working capital. Contractors carry retainage (a slice of each payment, often ~5–10%, held back until the job finishes) and finance materials and payroll ahead of progress billings, so growth consumes cash — watch operating cash flow relative to reported earnings.

How owners actually get ahead: win bids with accurate estimates, keep crews productive and utilized, shift mix toward recurring service, capture change orders, and — at scale — prefabricate and modularize assemblies off-site to cut expensive field hours. For private owners, the business also builds equity value that can be sold to a strategic or private-equity buyer (Section 8).

6. What drives demand

Demand tracks construction and, increasingly, electricity itself.

• Data centers / AI. The dominant near-term driver. From early 2024 through late 2025, data centers accounted for over 70% of the increase in private nonresidential construction spending, and one industry forecast sees U.S. data-center power demand climbing from roughly 24 gigawatts (GW) toward 110 GW by 2030. [7] Lawrence Berkeley National Laboratory estimates data centers could consume 11.8% of total U.S. electricity by 2030, and the U.S. Energy Information Administration (EIA) expects national electricity use to rise about 1% in 2026 and 3% in 2027, with large computing facilities a major driver. [8][9] These are electrically intensive megaprojects — switchgear, busway, redundancy, grounding — that favor large contractors able to staff and prefab at scale.
• Grid modernization and load growth. The Department of Energy's 2023 National Transmission Needs Study flagged aging infrastructure, insufficient transmission capacity, reliability, and generation interconnection as national needs — making utilities and power developers customers for transmission, distribution, substation, grid-hardening, and storm-restoration work. [10]
• Domestic manufacturing / reshoring. New semiconductor "fabs," battery plants, and other advanced-manufacturing facilities are power-hungry and electrical-labor-intensive; public contractors report rising industrial activity. [9][18]
• Electrification and clean energy. EV charging, heat pumps, all-electric buildings, solar, and storage each add electrical scope; the realized benefit depends on permitting, utility interconnection, financing, and incentives.
• New construction and renovation. Commercial and residential building volume — the traditional base — is sensitive to interest rates. Lower rates support more starts; higher rates cool them.
• Recurring service. Aging building stock needs ongoing maintenance, retrofits, and emergency restoration regardless of the construction cycle — the industry's most stable, highest-margin demand, which softens but does not eliminate cyclicality. [18]

7. Regulation

Electrical work is heavily regulated at the state and local level, which is part of why the industry stays fragmented:

• Licensing. Most states and municipalities license electricians (apprentice → journeyman → master) and require a contractor to hold or employ a licensed master electrician, plus apprenticeship, continuing education, permits, and inspections. Licenses are geographic and don't transfer freely, which protects local incumbents and makes compliance expertise valuable. [5]
• Codes and inspection. Work must meet the National Electrical Code (NEC), published as NFPA 70 by the National Fire Protection Association — adopted, often with local amendments, across the country — and pass municipal permitting and inspection. Contractors must manage code differences across markets. [12]
• Safety. The Occupational Safety and Health Administration (OSHA) governs construction electrical safety, chiefly under 29 Code of Federal Regulations (CFR) Part 1926, Subpart K (wiring methods, grounding, hazardous locations, lockout/tagout, worker protection). Electrical work carries real shock, arc-flash, and fall hazards, and safety records affect insurance and bidding. [11]
• Federal public-works labor and financial rules. Davis-Bacon prevailing-wage requirements generally apply to covered federal construction, alteration, and repair contracts exceeding $2,000. [13] Federal performance and payment bonds are generally required for construction contracts exceeding $150,000, with alternative payment protections for some contracts above $35,000 and up to $150,000. [14] SBA size standards (with affiliate rules) govern eligibility for federal small-business contracting programs. [3] Union (IBEW/NECA) versus merit-shop status also shapes labor cost and which projects a contractor can bid.
• Bonding and insurance. Larger jobs require surety bonds and substantial liability coverage — a barrier for small firms scaling up.
• Trade policy. Tariffs and supply constraints on electrical equipment (transformers, switchgear, conductors) affect material costs and lead times — an increasingly live issue during the data-center surge.

8. Competitive dynamics and consolidation

The federal concentration data (CR4 of 4.8%, HHI of 11.6) says it plainly: competition is local and intense, and no one dominates. [2] Customers weigh price, schedule reliability, safety records, technical expertise, bonding capacity, labor access, and prior relationships with general contractors, utilities, and owners. Barriers to entry are modest at the small end (a licensed electrician with a truck) but rise sharply with size — bonding capacity, skilled-labor access, and the ability to staff megaprojects create real scale advantages for the largest firms, especially on data-center work where national footprint and prefabrication matter.

Consolidation is the defining trend — and note the federal concentration figures are from 2022 and predate several large acquisitions. Private equity now drives roughly 75% of electrical-contractor mergers and acquisitions (M&A), typically by forming a "platform" company and bolting on smaller local shops. [16] Deal volume ran hot into 2024 (~140 deals) before normalizing to ~99 in 2025. [16] Electrical deals have fetched 15–20% higher multiples than other specialty-contractor deals, with typical enterprise values around 6–8× EBITDA (earnings before interest, taxes, depreciation, and amortization) — higher for larger, service-heavy, data-center-exposed firms. [16][17]

Consolidation is driven by owner retirement and succession, the need for bonding capacity and working capital, national customers seeking multi-site service, procurement and prefabrication advantages, and cross-selling of electrical, mechanical, controls, and maintenance work. Strategic buyers are active alongside PE: Quanta bought Cupertino Electric for ~$1.54 billion (2024), EMCOR acquired Miller Electric for ~$876.8 million (2025), and MYR Group acquired Valley Electric and Comet Electric for $328 million (October 2025). [16][20][21] The through-line: buyers are paying up for specialized labor pools, data-center expertise, customer relationships, and regional licenses.

Editorial judgment. Consolidation should improve capabilities and purchasing power, but it does not guarantee better margins. An acquired shop still has to retain its project managers, preserve customer relationships, and avoid inherited claims or underpriced work.

9. Risks

• Labor is the binding constraint. A persistent shortage of licensed electricians, foremen, estimators, and project managers caps how much work the industry can take on and pushes up wages — the biggest single risk to margins and growth. [5]
• Fixed-price cost overruns. Bad estimates, material spikes, design errors, scope disputes, or subcontractor failures on lump-sum jobs can turn a profitable project into a loss. [15][18]
• Cyclicality and rates. Commercial, residential, and industrial construction volumes fall when interest rates rise and the economy slows; utility maintenance and emergency restoration are more resilient but still budget- and weather-dependent.
• Materials and supply chains. Copper, aluminum, steel, switchgear, and transformers can see price volatility and long lead times; tariffs and trade restrictions add pressure. [18]
• Working-capital and credit strain. Retainage, disputed change orders, milestone billing, and customer or general-contractor delays can consume cash even when reported revenue is growing. [18]
• Bonding, insurance, and litigation. Large projects require surety support and substantial coverage; a major accident or failed project can damage both liquidity and reputation.
• Customer / project concentration. For firms leaning hard into data centers, revenue increasingly depends on a few hyperscale customers and their capital-spending cycle.
• Demand overbuild. Data-center and manufacturing announcements do not always become completed projects — interconnection limits, power availability, permitting, financing, technology shifts, or cancellations can shrink the realized opportunity. (Forward-looking judgment.)
• Consolidation and leverage. Acquisitions create integration, goodwill, debt, and key-person risks; public investors also inherit exposure to the acquirer's broader businesses, while private investors face illiquidity and thinner disclosure.

10. How to invest, and the outlook

Public-market routes

Direct exposure is limited to the names in Section 4, and they are best treated as different exposure profiles, not interchangeable peers:

• Utility and grid exposure: Quanta (PWR), MYR Group (MYRG), MasTec (MTZ), Primoris (PRIM).
• Commercial, industrial, and mission-critical electrical: IES Holdings (IESC), MYR Group (MYRG), and EMCOR's (EME) electrical segment — the cleaner 238210 proxies.
• Electrical plus mechanical building systems: EMCOR (EME) and Comfort Systems USA (FIX).

Examine segment mix before applying valuation multiples: compare backlog quality, fixed-price exposure, margin trends, cash conversion, acquisition spending and leverage, customer concentration, and the share of work tied to data centers or utility programs. Price-to-earnings and enterprise-value-to-EBITDA multiples help only after adjusting for business mix and acquisition accounting; dividend yield is secondary to reinvestment capacity in a consolidating industry. Valuations across the group have re-rated sharply on data-center optimism (Comfort Systems, for instance, was up roughly 200% in the year to mid-2026 [19]), so entry price and expectations matter. For a diversified, lower-single-name-risk approach, a broad infrastructure ETF such as PAVE holds several of these together.

Private-market routes — a better fit for most of this industry

• Own or operate a local contractor, or buy one from an owner nearing retirement. With ~79,000 mostly small firms and a wave of retiring owners, the acquisition pipeline is deep.
• Back a private-equity roll-up (as a fund limited partner or platform co-investor) — the most active segment of the market. [16]
• Provide private credit backed by receivables, equipment, or contracted backlog; or finance an employee-ownership (ESOP) transition.
• Franchises and service brands (residential/light-commercial service) offer a more standardized on-ramp.

Private underwriting should focus on backlog quality, customer relationships, estimating controls, project-manager retention, the labor model, license coverage, bonding line, insurance history, working-capital needs, and the credibility of cost-to-complete estimates. A smaller shop with disciplined estimating and recurring service work can be safer than a larger one dependent on a few big fixed-price projects.

Outlook

The demand backdrop is the strongest in a generation: data centers, electrification, reshoring, and grid investment are all pulling in the same direction, and rising electricity demand is a structural, multi-year tailwind rather than a one-cycle spike. Reported indicators are constructive — EIA expects renewed electricity-demand growth, Lawrence Berkeley National Laboratory sees data centers becoming a material share of national power use, and BLS projects 9% electrician employment growth from 2024 to 2034. [5][8][9] The primary constraints are skilled-labor supply and interest-rate-sensitive construction volumes; the primary risk is that the data-center/AI capital-spending cycle, now doing much of the heavy lifting, cools faster than expected.

Editorial judgment. The most attractive part of the industry is likely the technically difficult electrical work tied to grid capacity, data centers, advanced manufacturing, and mission-critical facilities; general commercial and residential contracting stays more cyclical. Across both public and private markets, the winning businesses are those that convert strong demand into cash without sacrificing labor quality, pricing discipline, safety, or balance-sheet flexibility. For patient investors, the more durable value may lie in the fragmented private middle market — where recurring service, disciplined estimating, and consolidation economics compound quietly — rather than in the handful of already richly valued public names.

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Sources

1. U.S. Census Bureau, County Business Patterns (CBP), 2023 — NAICS 238210 establishments, employment, and payroll (via Histometrics ground-truth dataset). https://www.census.gov/data/datasets/2023/econ/cbp/2023-cbp.html
2. U.S. Census Bureau, 2022 Economic Census — Concentration of Largest Firms for the U.S., NAICS 238210 (receipts, firm count, CR4/CR8/CR20/CR50, HHI). https://data.census.gov/table/ECNSIZE2022.EC2200SIZECONCEN?codeset=naics~238210
3. U.S. Small Business Administration, Table of Size Standards, 2023 (NAICS 238210 = $19.0 million receipts; affiliate rules for federal contracting). https://www.sba.gov/document/support-table-size-standards
4. U.S. Census Bureau, 2022 NAICS: 238210 — Electrical Contractors and Other Wiring Installation Contractors (definition and exclusions). https://www.census.gov/naics/?details=238210&input=238210&year=2022
5. U.S. Bureau of Labor Statistics, Occupational Outlook Handbook: Electricians, 2025 (818,700 employed 2024; ~$62,000 median wage; 9% projected growth 2024–2034; ~81,000 annual openings). https://www.bls.gov/ooh/construction-and-extraction/electricians.htm
6. EC&M (Electrical Construction & Maintenance), 2025 Top 50 Electrical Contractors Rankings, 2025 (Quanta, Rosendin, EMCOR, MYR Group; $59.5B, +15%). https://www.ecmweb.com/top-50-electrical-contractors/article/55316333/2025-top-50-electrical-contractors-rankings
7. Grid Strategies LLC, National Load Growth Report 2025 (data-center-led power demand; ~24 GW→110 GW; >70% of the rise in private nonresidential construction spending). https://gridstrategiesllc.com/wp-content/uploads/Grid-Strategies-National-Load-Growth-Report-2025.pdf
8. Lawrence Berkeley National Laboratory, United States Data Center Energy Usage Report: 2025 Update (data centers up to 11.8% of U.S. electricity by 2030). https://eta-publications.lbl.gov/publications/united-states-data-center-energy-2025
9. U.S. Energy Information Administration, Short-Term Energy Outlook / electricity-demand release (U.S. electricity use +~1% in 2026, +~3% in 2027; data centers, semiconductor and battery factories as drivers). https://www.eia.gov/pressroom/releases/press582.php
10. U.S. Department of Energy, National Transmission Needs Study, 2023. https://www.energy.gov/sites/default/files/2023-12/National%20Transmission%20Needs%20Study%20-%20Final_2023.12.1.pdf
11. Occupational Safety and Health Administration, 29 CFR 1926 Subpart K — Electrical. https://www.osha.gov/laws-regs/regulations/standardnumber/1926/1926SubpartK
12. National Fire Protection Association, NFPA 70: National Electrical Code (NEC). https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=70
13. Acquisition.gov, FAR Subpart 22.4 — Labor Standards for Contracts Involving Construction (Davis-Bacon; >$2,000 threshold). https://www.acquisition.gov/far/subpart-22.4
14. Acquisition.gov, FAR Subpart 28.1 — Bonds and Other Financial Protections (performance/payment bonds >$150,000; alternatives $35,000–$150,000). https://www.acquisition.gov/far/subpart-28.1
15. Profitability Partners / Lightning Path Partners, Electrical Contractor Profit Margins (gross 26–34%, net 5–10% / 2.5–6% at smaller shops, service 45–55% gross), 2025–2026. https://profitabilitypartners.io/electrical-contractor-profit-margins/
16. Cascade Partners, Electrical Contracting and Utility Infrastructure M&A Update (H2 2025), 2026; and EC&M, "Electrical Contractor M&A Dips in 2025," 2025 (PE ~75% of deals; ~140 deals in 2024 → ~99 in 2025; MYR/Valley Electric & Comet Electric $328M, Oct 2025). https://cascade-partners.com/wp-content/uploads/2026/02/Electrical-Contracting-and-Utility-Infrastructure-MA-Update-H2-2025-vF.pdf; https://www.ecmweb.com/members/latest-news/article/55366163/electrical-contractor-ma-dips-in-2025
17. BMI Mergers & Acquisitions, Electrifying M&A Market for Electrical Contractors: 2024 Recap (~6–8× EBITDA multiples), 2025. https://www.bmimergers.com/2025/02/19/electrical-contractors-2024-recap/
18. Company SEC filings and FY results — Quanta Services (PWR), EMCOR Group (EME; electrical construction segment ~$3.6B; ~$14.6B 2024), Comfort Systems USA (FIX; $7.03B 2024), MasTec (MTZ), Dycom (DY), IES Holdings (IESC; $2.9B FY2024), MYR Group (MYRG; $3.36B 2024), Primoris Services (PRIM). Representative 10-Ks: https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=pwr&type=10-K; EMCOR https://www.sec.gov/Archives/edgar/data/105634/000010563426000025/eme-20251231.htm; MYR Group https://investor.myrgroup.com/news-releases; IES Holdings https://investors.ies-corporate.com/news-releases; Comfort Systems https://investors.comfortsystemsusa.com/news-releases
19. Market capitalizations as of ~July 2026 (stockanalysis.com / companiesmarketcap.com): PWR ~$99B, FIX ~$59B, EME ~$41B, MTZ ~$34B, DY ~$13B, IESC ~$12B, MYRG ~$6B, PRIM ~$6B, LMB ~$0.9B. https://stockanalysis.com/stocks/fix/market-cap/; https://stockanalysis.com/stocks/iesc/market-cap/; https://stockanalysis.com/stocks/myrg/market-cap/
20. Quanta Services, Quanta Services Acquires Cupertino Electric (~$1.54 billion), 2024. https://investors.quantaservices.com/news-events/press-releases/detail/360/quanta-services-acquires-cupertino-electric-inc-a-premier-electrical-infrastructure-solutions-provider-to-the-technology-and-renewable-energy-industries
21. EMCOR Group, 2025 Form 10-K / acquisition of Miller Electric (~$876.8 million), 2026. https://www.sec.gov/Archives/edgar/data/105634/000010563426000025/eme-20251231.htm
22. U.S. Census Bureau, Nonemployer Statistics (basis for the employer-only undercount caveat; count not included in the supplied ground-truth file). https://www.census.gov/data/developers/data-sets/nonemp-api.2022.html
23. Rosendin, Employee-Owned (100% ESOP), accessed 2026. https://www.rosendin.com/employee-owned/
24. Faith Technologies, Company History (team-member ownership), accessed 2026. https://www.faithtechinc.com/culture/history/
25. One Rock Capital Partners, Completes Sale of ArchKey Solutions to 26North, 2024; 26North fund announcement, 2026. https://www.onerock.com/wp-content/uploads/6728e6c9745e9c46cb4dfd90_One-Rock-Capital-Partners-Close-on-Sale-of-ArchKey-Solutions-to-26North_vF.pdf
26. Southland Industries, Ownership Succession (100% employee-owned), accessed 2026. https://southlandind.com/about/acquisitions