QUANTA SERVICES, INC. (PWR) Business

ITEM 1.Business

OVERVIEW

Quanta Services, Inc. (together with its subsidiaries, “Quanta,” “we,” “us” or “our”) is a leading provider of comprehensive infrastructure solutions for the electric and gas utility, power generation, large load center, manufacturing, communications, pipeline and energy industries in the United States, Canada, Australia and select other international markets. We provide design, engineering, procurement, construction, upgrade and repair and maintenance services for infrastructure within each of these industries, including electric power transmission and distribution networks; substation facilities; wind, solar and gas power generation and transmission and battery storage facilities; low voltage electrical, mechanical, plumbing and process infrastructure for large load centers, such as data center, advanced manufacturing, healthcare, pharmaceutical and industrial facilities; communications and cable multi-system operator networks; gas utility systems; pipeline transmission systems and facilities; and downstream industrial facilities. Our operations are decentralized and labor-intensive, and we rely on craft skilled labor personnel and experienced operators to successfully manage our day-to-day business. We also have an experienced management team, both at the executive and regional levels and within our subsidiaries, which we refer to as operating companies. We operate a fleet of owned and leased trucks and trailers, support vehicles and specialty construction equipment, as well as various proprietary technologies that enhance our service offerings. We have a large and diverse customer base, including many of the leading companies in the utility, renewable energy, hyperscaler, technology, communications, industrial and energy delivery markets.

The performance of our business generally depends on our ability to obtain contracts with customers and to effectively deliver the services provided under those contracts. Our services are typically provided pursuant to master service agreements (MSAs), repair and maintenance contracts and fixed price and non-fixed price construction and engineering contracts. We offer comprehensive and diverse solutions on a broad geographic scale and have a solid base of long-standing customer relationships in each of the industries we serve. We believe our reputation for safety leadership, responsiveness and performance, geographic reach, comprehensive service offerings and financial strength have resulted in strong relationships with numerous customers, and we endeavor to develop and maintain strategic alliances and preferred service provider status with our customers.

We believe that our business strategies, along with our safety culture and financial resources, differentiate us from our competition and position us to benefit from future programmatic and capital spending by our customers. Our strategies include delivering and continuing to expand our portfolio of infrastructure solutions to existing and potential customers, developing our technological and training capabilities, remaining committed to the safety of our employees, and maintaining an entrepreneurial culture throughout our organization. We believe executing on these strategies places us in the position to be a solutions provider to our customers and capitalize on opportunities and trends in the industries we serve and expand our operations to select new markets.

SEGMENTS

During the three months ended March 31, 2025, Quanta’s Chief Executive Officer reevaluated how performance of the business is assessed and how resources are allocated, which resulted in a change in the reporting of management’s internal financial information. As a result, beginning with the three months ended March 31, 2025, Quanta began reporting the results of its two operating segments, which are also its two reportable segments: (1) Electric Infrastructure Solutions (Electric) and (2) Underground Utility and Infrastructure Solutions (Underground and Infrastructure). The Electric segment consists of the historical Electric Power Infrastructure Solutions and the Renewable Energy Infrastructure Solutions segments. In conjunction with this change, certain prior period amounts have been recast to conform to this new segment reporting structure.

Our entrepreneurial business model allows multiple operating companies to serve the same or similar customers and to provide a range of services across end user markets. Reportable segment information, including revenues and operating income by type of work, is gathered from each operating company. Classification of operating company revenues by type of work for segment reporting purposes can require judgment on the part of management.

We operate primarily in the United States; however, we derived approximately 7.0%, 8.7% and 14.2% of our revenues from foreign operations, primarily in Canada and Australia, during the years ended December 31, 2025, 2024 and 2023.

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Electric

Services

Our Electric segment provides comprehensive services primarily for the electric power grid, power generation and large load center markets. We believe our collaborative, customer-focused, and solutions-based approach, combined with our significant capabilities and scale, differentiate us in the marketplace. Services performed generally include:

•design, procurement, new construction, upgrade and repair and maintenance services for electric power transmission and distribution infrastructure, both overhead and underground, and substation facilities, along with other engineering and technical services, including services that support the implementation of upgrades by utilities to modernize and harden the electric power grid in order to ensure its safety and enhance reliability, to interconnect and transmit electricity from power generation and battery storage facilities and to accommodate increased residential and commercial use of electric vehicles;

•engineering, procurement, new construction (EPC), repowering and repair and maintenance services for renewable generation facilities, such as utility-scale wind, solar and hydropower generation facilities and battery storage facilities;

•emergency restoration services, including the repair of infrastructure damaged by fires and inclement weather;

•energized installation, maintenance and upgrade of electric power infrastructure utilizing our bare hand and hot stick methods and our robotic arm techniques;

•installation of “smart grid” technologies on electric power networks;

•design and installation of electrical systems for large load centers, such as data center, advanced manufacturing and industrial facilities;

•design and construction services to wireline and wireless communications companies, cable multi-system operators, technology companies and other customers within the communications industry;

•design, installation, maintenance and repair services related to commercial and industrial wiring; and

•aviation services primarily for the utility industry, including transportation of line workers, pole and tower setting, and wire stringing, as well as certain emergency aerial firefighting services.

This segment also includes (i) the majority of the financial results of our advanced training facility and our postsecondary educational institution, which specializes in pre-apprenticeship training, apprenticeship training and specialized utility task training for electric workers, as well as training for the gas distribution and communications industries; (ii) our portion of earnings of our unconsolidated integral affiliates, which includes, among others, our 50% equity interest in LUMA Energy, LLC (LUMA), a joint venture that was selected to operate, maintain, and modernize the approximately 18,000-mile electric transmission and distribution system in Puerto Rico; as well as our investment in a company that specializes in harvesting, treating and manufacturing wood utility poles and laminated wood products for utility and telecommunication companies; and (iii) financial results associated with our power transformer, circuit breaker and other manufacturing operations.

Business Environment

With respect to our electric infrastructure service offerings, utility and other customers are continuing to invest significant capital in their infrastructure systems and programs. Our utility customers continue to face increased demand for electricity, including as a result of electrification trends and increased demand for data center and other technology infrastructure and advanced manufacturing facilities. To accommodate this growth, we expect continued demand for new or expanded transmission, substation and distribution infrastructure to reliably transport power to meet demand driven by electrification, data centers and manufacturing reshoring, as well as the modification and reengineering of existing infrastructure with increasing penetration of renewable generation and battery storage and the increased investment in new gas-powered generation. Furthermore, in order to reliably and efficiently deliver power and in preparation for emerging technologies, utility customers are also integrating smart grid technologies into distribution systems to improve grid management and create efficiencies, and a number of utility customers continue to implement system upgrades and hardening programs in response to recurring severe weather events, including, among other things, initiatives to underground critical infrastructure. For example, utilities throughout the United States are executing storm hardening programs to make their systems more resilient to hurricanes and other severe weather events, and there are significant system resiliency initiatives underway in California and other regions in the United States that are designed to prevent and manage the impact of wildfires.

In addition, utility and other customers are increasing their investment in various forms of power generation in response to load growth expectations, which have accelerated based on demand for electricity driven by data centers, manufacturing and reshoring, industrialization, electrification and power grid expansion. Due to increased adoption and technological

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advancements and efficiencies, renewable generation has some of the lowest levelized costs of energy in the marketplace. When coupled with consumer and corporate preferences for clean energy and emissions-reduction initiatives, demand for renewable generation, energy storage, and related infrastructure has increased and is expected to result in sizable, long-term investments. Utility and other customers are also increasing their investments in other forms of base load power generation, such as combined cycle gas generation and gas peaker generation plants.

The development of power generation infrastructure can often necessitate the development and construction of related infrastructure, including high-voltage electric transmission and substation infrastructure, that is necessary to enhance grid resiliency and interconnect and transmit electricity from new generation facilities into the existing electric power grid. In addition, the investment of capital into the build out of data centers by technology customers in order to, among other things, expand cloud-based services and develop artificial intelligence (AI) training and inference, increases demand for our solutions offerings. In particular, we believe Quanta is well positioned to provide turnkey infrastructure solutions for these facilities, such as critical-path low-voltage electrical infrastructure solutions inside data centers (e.g., advanced manufactured and modular solutions); high-voltage substation, transformer and transmission interconnection infrastructure to connect the facilities to the power grid; and generation infrastructure necessary to power the facilities. These overall market dynamics support demand for our capabilities and our solutions-based approach for our high-quality customers.

With respect to our communications service offerings, which are focused on the North American market, consumer and commercial demand for communication and data-intensive, high-bandwidth wireline and wireless services and applications are driving significant investment in infrastructure and the deployment of new technologies. In particular, we believe there are opportunities to provide fiber and other services in and around data centers, and to interconnect data centers. Communications providers are utilizing fifth generation wireless (5G) infrastructure to support fixed wireless access, which is driving additional fiber capacity requirements for consumer and commercial applications. Additionally, legislative and regulatory initiatives, including the Broadband Equity Access and Deployment (BEAD) Program, have dedicated billions of dollars of funding to support broadband service to underserved markets.

Underground and Infrastructure

Services

Our Underground and Infrastructure segment provides comprehensive infrastructure solutions to customers involved in the transportation, distribution, storage, development and processing of natural gas, oil and other products, as well as customers that own and operate large load centers. Services performed generally include:

•design, engineering, procurement, new construction, upgrade and repair and maintenance services for natural gas systems for gas utility customers;

•pipeline protection, integrity testing, rehabilitation and replacement services;

•catalyst replacement services, high-pressure and critical-path turnaround services, instrumentation and electrical services, piping, fabrication and storage tank services for the midstream and downstream industrial energy markets, as well as specialty cleaning and environmental solutions for the industrial energy and petrochemical markets;

•engineering and construction services for pipeline systems, storage systems and compressor and pump stations and the fabrication of pipeline support systems and related structures and facilities;

•trenching, directional boring and mechanized welding services related to the services described above;

•civil solutions, including site clearing, earthwork, soil stabilization and infrastructure development;

•turnkey mechanical, plumbing and process infrastructure solutions for large load centers in the technology, semiconductor, healthcare and other industries; and

•engineering, construction and maintenance services for energy transition and carbon-reduction related projects, such as alternative fuel facilities, carbon capture systems and hydrogen facilities.

Business Environment

With respect to gas utility services, pipeline integrity and transmission services and downstream industrial services, we believe these are specialty services and industries that are driven by regulated utility spending; regulation, replacement and rehabilitation of aging infrastructure; and safety and environmental initiatives. We believe this provides a greater level of business sustainability and predictability and helps to offset the cyclicality of larger pipeline projects described below. Natural gas utilities have implemented multi-decade modernization programs to replace aging cast iron, bare steel and plastic system infrastructure with modern materials for safety, reliability and environmental purposes, and regulatory measures have increased the frequency and stringency of pipeline integrity testing requirements that require our customers to test, inspect, repair, maintain and replace pipeline infrastructure to ensure that it operates in a safe, reliable and environmentally conscious manner.

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Further, permitting challenges associated with construction of new pipelines can make existing pipeline infrastructure more valuable, motivating owners to extend the useful life of existing pipeline assets through integrity initiatives. Additionally, with respect to our downstream industrial services, including our high-pressure and critical-path turnaround services, as well as our capabilities with respect to instrumentation and electrical services, piping, fabrication and storage tanks services, and other industrial services, we are focused on processing facilities located along the U.S. Gulf Coast region, which we believe should have certain long-term strategic advantages due to their proximity to competitively priced and abundant hydrocarbon resources.

Our revenues related to larger pipeline services have fluctuated in recent years. For example, revenues associated with larger U.S. pipeline projects have declined significantly as the pipeline and related infrastructure development necessary to support U.S. shale formations has largely been completed in the near term and as a result of a more challenging permitting and regulatory environment. Revenues associated with large pipeline projects have decreased in recent years, as compared to prior years, and we anticipate that revenues associated with these projects will continue to fluctuate. Despite these fluctuations and cyclicality, we continue to selectively pursue larger pipeline project opportunities to the extent they satisfy our margin and risk profiles. Additionally, the significant increase in demand for electric power is resulting in an increase in planning for new natural gas generation facilities, as well as delays in the retirement of existing facilities, which could in turn increase the demand for additional pipeline, related infrastructure and integrity services.

Through recent acquisitions we have expanded our capabilities and solutions related to turnkey mechanical, plumbing and process infrastructure solutions, which we believe position us to meet strong demand for these services by data center, manufacturing, semiconductor and other large load facilities and provide opportunities in other core end markets. We have also expanded our capabilities and solutions related to civil solutions through recent acquisitions, which allows us to meet strong demand for these services.

We also believe that customers in this segment are implementing strategies to reduce carbon emissions produced from their operations, which are providing incremental opportunities for our services and could include building or repurposing pipeline infrastructure, including the development of infrastructure for blending hydrogen into natural gas flow and carbon capture projects. To the extent these technologies gain wider adoption, we believe our customer relationships and capabilities position us well to capitalize on future opportunities. Furthermore, the favorable characteristics of natural gas could also position North America as a leading competitor in the global LNG export market, which could provide additional opportunities for our pipeline service offerings.

GENERAL

Recent Acquisitions

On July 25, 2025, we completed the acquisition of Dynamic Systems (DSI), LLC (Dynamic Systems), which provides turnkey mechanical, plumbing and process infrastructure solutions to a diversified customer base that includes technology, semiconductor, healthcare and other load center markets. Dynamic Systems is located in the United States, and its results have been included primarily in the Underground and Infrastructure segment. During the year ended December 31, 2025, we also acquired seven additional businesses, including two businesses located in the United States that specialize in civil solutions, including site clearing, earthwork, soil stabilization and infrastructure development (which have been included in the Underground and Infrastructure segment), a business located in Australia that specializes in electrical engineering and the design and manufacturing of industrial technology solutions (which has been included in both the Electric and Underground and Infrastructure segments), a business located in the United States that specializes in utility construction and related support services (which has primarily been included in the Electric segment), a business located in the United States that specializes in the design, construction and repair of overhead and underground transmission and distribution infrastructure, civil construction services related to substations, as well as helicopter services for electric utility infrastructure (which has primarily been included in the Electric segment), a business located in the United States that specializes in electrical solutions including low voltage technology, testing, engineering, integration, renewable energy and electric prefabrication solutions (which has primarily been included in the Electric segment) and a business located in the United States that provides helicopter services (which has primarily been included in the Electric segment and was accounted for as an asset acquisition).

On July 17, 2024, we completed the acquisition of Cupertino Electric, Inc. (CEI), which provides electrical infrastructure solutions, including engineering, procurement, project management, construction and modularization services, to the technology, renewable energy and infrastructure and commercial industries. CEI is located in the United States, and its results have been included in the Electric segment. During the year ended December 31, 2024, we also acquired seven additional businesses located in the United States, including: a business that provides specialty environmental solutions to utility, industrial and petrochemical companies (primarily included in the Underground and Infrastructure segment); a business that specializes in testing, manufacturing and distributing safety equipment and supplies (primarily included in the Electric segment); a business that specializes in electrical infrastructure services for substations, data centers and governmental entities (primarily included in the Electric segment); a business that manufactures transmission and distribution equipment for the

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electric utility industry (primarily included in the Electric segment); a business that provides services and equipment related to aerial telecommunications infrastructure and networks (primarily included in the Electric segment); a business that provides services related to fiber optic networks (primarily included in the Electric segment); and a business that specializes in designing, manufacturing, and distributing liquid-filled power transformers primarily for electrical companies and utilities (primarily included in the Electric segment).

During the year ended December 31, 2023, we acquired five businesses located in the United States that are primarily included in the Electric segment including: a business that provides services related to high-voltage transmission lines, overhead and underground distribution, emergency restoration and industrial and commercial wiring and lighting; a business that procures parts, assembles kits for sale, manages logistics and installs solar tracking equipment for utility and development customers; a business that provides concrete construction services; a business specializing in power studies, maintenance testing and commissioning primarily for utility and commercial customers and a business that manufactures power transformers for the electric utility, renewable energy, municipal power and industrial markets.

The results of operations of acquired businesses have been included in our consolidated financial statements since their respective acquisition dates. These acquisitions are further described in Note 6 of the Notes to Consolidated Financial Statements in Item 8. Financial Statements and Supplementary Data in Part II of this Annual Report.

We believe potential acquisition and investment opportunities exist in our industries and adjacent industries. We believe our business model, strong customer relationships and employee-centric culture are attractive to potential acquisition targets. While the attractiveness of certain acquisition targets may be diminished in the short term by increased interest rates, regulatory conditions and market volatility, we continue to evaluate opportunities that are expected to, among other things, broaden our customer base, expand our geographic area of operations and grow and diversify our portfolio of products and services.

Customer Relationships

We have a large and diverse customer base, including many of the leading companies in the industries we serve, and we have developed strong strategic alliances with numerous customers and strive to develop and maintain our status as a preferred solutions provider to our customers. For the year ended December 31, 2025, our largest customer accounted for 8% of our consolidated revenues and our ten largest customers accounted for 30% of our consolidated revenues. Representative customers include:

Our customers include utility, power developer, technology, communications, and energy delivery companies, as well as governmental entities. We have estimated revenues by customer type as a percentage of total revenues below. Such estimates

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are based on management judgment and assumptions and are provided to show perceived trends in our customer types and should be considered directional in nature.

The customer types set forth in the table above are described in further detail as follows:

•Utility and Power - Customers that are electric and gas utility companies, as well as power developers;

•Energy and Other - Customers that own refineries or petrochemical plants and customers that own and/or operate pipelines for the delivery of hydrocarbons, and other non-utility and power customers and non-technology, manufacturing and communications customers to which we provide solutions; and

•Technology, Manufacturing and Communications - Customers that own and/or operate assets supporting delivery of data, communications and digital services (such as hyperscaler, data center colocation) and customers who own or operate commercial or industrial manufacturing facilities, as well as telecommunication customers.

We believe utility, power developer, technology, communications, and energy delivery company customers provide us with growth opportunities due to their programmatic and long-term capital programs and/or the longer-term trends and transitions associated with these industries. We are a preferred service provider for many of our customers, which generally means we have met minimum standards for a specific category of service, maintained a high level of performance and agreed to certain payment terms and negotiated rates. We strive to maintain our preferred status as we believe it provides us an advantage in the award of future work for the applicable customer. Furthermore, many of our strategic relationships with customers take the form of strategic alliance or long-term maintenance agreements, which typically extend for an initial term and may include renewal options to extend the initial term. Strategic alliance agreements also generally state an intention to work together over a period of time and/or on specific types of projects, and many provide us with preferential bidding procedures. We have also developed manufacturing capabilities designed to provide us with the capability to produce certain critical project components, including power transformers, that are needed for our customers’ projects.

Although we have an integrated marketing and business development strategy, management at each of our operating companies is primarily responsible for developing and maintaining successful long-term relationships with customers. Our operating company management teams build upon existing customer relationships to secure additional projects and increase revenues. Many of these customer relationships are long-standing and are maintained through a partnering approach with centralized account management, which includes project evaluation and consulting, quality performance, performance measurement and direct customer contact. Additionally, operating company management focuses on pursuing growth opportunities with prospective customers. We also encourage operating company management to cross-sell services of our other operating companies to their customers and coordinate with our other operating companies to pursue projects, especially those that are larger and more complex. We believe our ability to provide services that cover a broad spectrum of our customers’ needs and requirements is a significant differentiator. Our corporate-level business development and regional management groups support these activities by promoting and marketing our services for existing and prospective large accounts, as well as projects that are capable of utilizing services from multiple operating companies.

Competition and Market Demand

The industries and geographic markets in which we operate are highly competitive, and several of our competitors are large companies that have significant financial, technical and marketing resources. In addition, there are relatively few barriers to entry into some of the industries in which we operate and, as a result, organizations that have adequate financial resources and access to technical expertise may become a competitor. Furthermore, companies that we engage as subcontractors, including pursuant to certain regulatory and customer requirements, may develop the expertise necessary to compete with us with respect to the award of prime contracts from our customers.

A significant portion of our revenues is currently derived from unit price or fixed price agreements, and price is often an important factor in the award of such agreements. Accordingly, we could be underbid by our competitors. However, customers often consider other factors in choosing a service provider, including technical expertise and experience, breadth of solutions offerings, safety ratings, financial and operational resources, geographic presence, industry reputation and dependability, which we expect to benefit larger service providers such as us. In addition, competition may lessen as industry resources, such as labor supplies, approach capacity. There can be no assurance, however, that our competitors will not develop the expertise,

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experience and resources to provide services that are superior in both price and quality to our services, or that we will be able to maintain or enhance our competitive position. The in-house service organizations of certain of our existing or prospective customers, primarily our utility customers, employ personnel who perform some of the same types of services we provide. Although these companies currently outsource a significant portion of these services, there can be no assurance that they will continue to do so in the future or that they will not acquire additional in-house capabilities.

For further information regarding the effects of competition on our business and trends in market demand affecting our business, see Risks Related to Operating Our Business and Risks Related to Our Industries in Item 1A. Risk Factors in Part I of this Annual Report and Results of Operations in Item 7. Management’s Discussion and Analysis of Financial Condition in Part II of this Annual Report.

Material Resources

Equipment

We depend on the availability of a wide range of equipment to perform our services. We operate a fleet of owned and leased trucks and trailers, as well as support vehicles and specialty construction equipment, such as bucket trucks, digger derricks, sidebooms, dozers, backhoes, excavators, trenchers, generators, boring machines, cranes, robotic arms, wire pullers and tensioners. We also own a large fleet of aircraft, primarily helicopters, that are utilized in connection with our solution offerings. As of December 31, 2025, the total size of our owned and leased fleet was approximately 80,000 units. A number of factors that we may not be able to predict or control could result in increased costs for, or delays in delivery of, this equipment, including supply chain and other logistical challenges, as well as global trade relationships and other general market and political conditions that could impact production, delivery or pricing of such equipment (e.g., inflation, interest rates, recessionary economic conditions). Additionally, our ability to efficiently allocate equipment, including our vehicle fleet and helicopters, across our operating companies may impact our ability to perform services and the profitability of our operations. As such, we have invested, and continue to invest, significant resources and management attention to the utilization of our equipment.

Project Materials

We and our customers depend on the availability of certain materials for construction, upgrade, repair and maintenance of their infrastructure, including, among other things, steel, copper, aluminum, and components for electrical projects (e.g., power transformers, circuit breakers, wire) and power generation projects (e.g., solar panels, wind turbine blades, batteries). While our customers are typically responsible for supplying most or all of the materials required for the services we perform on their projects, pursuant to certain of our contracts, including contacts for our comprehensive EPC services, we are required to procure all or part of the materials needed for a project. As we continue to expand our EPC services, customers are increasingly requesting that we be responsible for procuring materials, and this trend is expected to continue to increase.

Additionally, we have invested in domestic manufacturing capabilities for certain critical transmission and power generation components, including high- and low-voltage power transformers, and we have made strategic investments in other core utility infrastructure equipment, including utility poles. We believe continuing to develop these capabilities and make these investments can help alleviate certain of our customers’ supply chain constraints and improve and control project timelines, as well as potentially reduce exposure to changes in global trade relationships around such components.

For further information regarding certain risks associated with sources and availability of project materials and components, see Regulation below and Risks Related to Operating Our Business in Item 1A. Risk Factors in Part I of this Annual Report.

Seasonality and Cyclicality

Typically, our revenues and results of operations can be subject to seasonal and other variations. These variations are influenced by, among other things, weather, customer spending patterns, bidding seasons, receipt of required regulatory approvals, permits and rights of way, project timing and schedules, and holidays. Our revenues are generally lowest in the first quarter of the year because cold, snowy or wet conditions can create challenging working environments that are more costly for our customers or cause delays on projects. In addition, infrastructure projects often do not begin in a meaningful way until our customers finalize their capital budgets, which typically occurs during the first quarter. Second quarter revenues are typically higher than those in the first quarter, as some projects begin, but continued cold and wet weather can often impact productivity. Third quarter and fourth quarter revenues are typically the highest of the year, as a greater number of projects are underway and operating conditions, including weather, are normally more accommodating. During the fourth quarter, projects are often completed and customers often seek to spend their capital budgets before year end. However, the holiday season and inclement weather can sometimes cause delays during the fourth quarter, reducing revenues and increasing costs. These seasonal impacts are typical for our U.S. operations, but seasonality for our international operations may differ.

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Regulation

Compliance with numerous regulations has a material effect on our operations. Our operations are subject to various federal, state, local and international laws and regulations, including:

•licensing, permitting and inspection requirements applicable to contractors and engineers;

•regulations relating to worker safety (e.g., Occupational Safety and Health Administration regulations) and environmental protection;

•permitting and inspection requirements applicable to construction projects;

•wage and hour regulations (e.g., Fair Labor Standards Act) and regulations associated with our collective bargaining agreements and unionized workforce;

•regulations relating to sourcing and transportation of equipment and materials, including licensing and permitting requirements;

•regulations regarding engagement of suppliers and subcontractors that meet diversity-ownership or disadvantaged-business requirements;

•regulations relating to aviation activities;

•building and electrical codes;

•applicable U.S. and non-U.S. anti-corruption regulations;

•immigration regulations applicable to U.S. and cross-border employment; and

•special bidding, procurement, cybersecurity and other requirements on government projects, as well as obtaining and maintaining security clearance required for certain government projects.

We believe that we are in compliance with all material licensing and regulatory requirements that are necessary to conduct our operations. Our failure to comply with applicable regulations could result in substantial fines or revocation of certain of our operating licenses, as well as give rise to termination or cancellation rights under our contracts or disqualify us from future bidding opportunities. We are also subject to numerous federal, state, local and international environmental laws and regulations governing our operations, including the handling, transportation and disposal of non-hazardous and hazardous substances and wastes, as well as emissions and other discharges into the environment, including discharges to air, surface water, groundwater and soil. We also are subject to laws and regulations that impose liability and cleanup responsibility for releases of hazardous substances into the environment. Under certain of these laws and regulations, liability can be imposed for cleanup of previously owned or operated properties or currently owned properties at which hazardous substances or wastes were discharged or disposed of by a former owner or operator, regardless of whether we directly caused the contamination or violated any law at the time of discharge or disposal. The presence of contamination from such substances or wastes could also interfere with ongoing operations or adversely affect our ability to sell or lease the property or use it as collateral for financing. In addition, we could be held liable for significant penalties and damages under certain environmental laws and regulations or be subject to revocation of certain licenses or permits, which could materially and adversely affect our business, results of operations and cash flows. Our contracts with customers may also impose liability on us for environmental issues that arise through the performance of our services. As a result, from time to time, we incur, and expect to continue to incur, costs and obligations to remain in compliance with applicable environmental laws and regulations, to correct environmental noncompliance matters and for remediation at or relating to certain of our properties. We believe that we are in substantial compliance with our environmental obligations and that any such obligations will not have a material adverse effect on our business or financial performance.

The overall regulatory environment also creates both challenges and opportunities for our business. In recent years, certain of our projects and certain customer spending in our industries have been negatively impacted by regulatory and permitting delays, as well as private legal challenges related to regulatory requirements, particularly with respect to large transmission and pipeline projects. Any tariffs, duties, taxes, assessments, or other limitations on the availability or sourcing of materials or components for our customers’ projects can also increase costs for customers and create variability of project timing. For example, regulatory, legislative or executive action with respect to regional and global trade relationships have impacted, and may impact in the future, the supply chain for certain components required for our customers’ projects (e.g., solar panels). For further information regarding the effects of regulation on our business, see Risks Related to Operating Our Business and Risks Related Regulation and Compliance in Item 1A. Risk Factors in Part I of this Annual Report.

Conversely, we believe that there are also several existing, pending or proposed legislative or regulatory actions that may alleviate certain regulatory and permitting issues and positively impact long-term demand, particularly in connection with electric power infrastructure and power generation spending. For example, regulatory changes affecting siting and right-of-way processes could potentially accelerate construction for transmission projects, and state and federal reliability standards are creating incentives for both electrical and pipeline system investment and maintenance.

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Human Capital Resources

We believe our employees are our most important resources, and we focus significant attention and resources on attracting, developing and retaining talented and experienced individuals. We believe our industry-leading training and safety programs are a strength and competitive differentiator with not only our current and potential operating company employees, but with our customers, which have high safety standards and are increasing the amount of their outsourced infrastructure services. Our operations are decentralized and labor-intensive, and we rely on craft skilled labor personnel and experienced operators to successfully manage our day-to-day business, as well as corporate management and professional personnel to coordinate and help execute our business strategies, allocate capital and coordinate equipment usage, and facilitate certain centralized administrative services.

Employee Profile

As of December 31, 2025, we had approximately 69,500 employees, consisting of approximately 13,800 salaried employees, including, among others, executive officers, professional and administrative staff, project managers and engineers, job superintendents and field personnel, and approximately 55,700 hourly employees, the number of which fluctuates depending upon the number and size of the projects that are ongoing and planned at any particular time. Additionally, approximately 36% of our employees as of December 31, 2025 were covered by collective bargaining agreements, which require the payment of specified wages, the observance of certain workplace rules and the payment of certain amounts to multiemployer pension plans and employee benefit trusts. These collective bargaining agreements have varying terms and expiration dates, and the majority contain provisions that prohibit work stoppages or strikes, even during specified negotiation periods relating to agreement renewals, and provide for binding arbitration dispute resolution in the event of prolonged disagreement. As of December 31, 2025, we had approximately 64,400 U.S. employees and approximately 5,100 non-U.S. employees, with the majority of our non-U.S. employees based in Canada.

Employee Health and Safety

Performance of our services requires the use of heavy equipment and exposure to inherently hazardous conditions. In response to these inherent hazards and as part of our commitment to the safety of our operating company employees, customers and third parties, our corporate and operating company management personnel have established safety programs, policies and procedures and ongoing training requirements for our employees and have also developed and implemented critical safety equipment and innovations. For example, on our project sites we have implemented emergency response plans, personal voltage detectors, first aid training and automated external defibrillators, which have helped save the lives of our employees and bystanders. We have also continued to invest significant resources in our safety programs and training facilities, including the Quanta Advanced Training Center, located in Texas, and our safety monitoring tools, including fleet management software. Our operating companies also develop and share best practices for safety policies and practices, and we have an established program for onboarding newly acquired companies and working with them to augment their existing safety practices as necessary. We are also subject to, and must comply with, extensive regulations relating to worker health and safety, including the regulations of the Occupational Safety and Health Administration.

Employee Recruiting, Development and Training

Our success depends on our ability to attract, develop and retain highly qualified employees, including craft skilled labor, project management, engineers, architects, designers, management and professional and administrative employees.

Craft Skilled Labor. We continue to address the longer-term need for additional labor resources in our markets, as our customers continue to seek additional specialized labor resources to address an aging utility workforce and longer-term labor availability issues, increasing pressure to reduce costs and improve reliability, and increasing duration and complexity of their capital programs. We believe these trends will continue, possibly to such a degree that demand for labor resources will outpace supply. Furthermore, the increased demand for our services based on favorable dynamics in certain of our industries can create shortages of qualified labor. In order to take advantage of available opportunities and successfully implement our long-term strategy, we must be able to employ, train and retain the necessary skilled personnel. As a result, we are taking proactive steps to develop our workforce, including through strategic relationships with universities, the military and unions and the expansion and development of our training facilities and postsecondary educational institution. For example, we own and operate Northwest Lineman College, a postsecondary educational institution that provides training programs for the electric power infrastructure, communications and underground utility and infrastructure industries and specializes in pre-apprenticeship training, apprenticeship training and specialized utility task training for electric workers. We also continue to invest in our education and training capabilities at the Quanta Advanced Training Center and other dedicated training facilities, which provide programs for, among other things, beginning linemen, energized electric power services, telecommunications services, renewable (solar) construction, industrial services, wireman introduction, lead and cable splicing, directional drilling, gas distribution services and pipeline integrity training. These training facilities allow us to provide classroom and on-the-job

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training programs and allow us to train employees in a controlled environment on a large variety of industry common structures.

As an example of our strategic relationships with unions, our operating companies performing more sophisticated and technical jobs utilize, when applicable, training programs provided by the International Brotherhood of Electrical Workers/National Electrical Contractors Associations (IBEW/NECA) Apprenticeship Program, training programs sponsored by the four trade unions administered by the Pipe Line Contractors Association (PLCA), apprenticeship training programs sponsored by the Canadian Union of Skilled Workers (CUSW) or our equivalent programs. Certain of our operating companies have also established apprenticeship training programs approved by the U.S. Department of Labor that prescribe equivalent training requirements for employees who are not otherwise subject to the requirements of the IBEW/NECA Apprenticeship Program. In addition, the Laborers International Union of North America, the International Brotherhood of Teamsters, the United Association of Plumbers and Pipefitters and the International Union of Operating Engineers have training programs specifically designed for developing and improving the skills of their members who work in the pipeline construction industry. Our operating companies also share best practices for training and educational programs. Although we believe these and other initiatives will help address workforce needs, meeting our customers’ demand for labor resources could prove challenging. For additional information on the risks associated with labor resources in our industries, see Risks Related to Operating Our Business in Item 1A. Risk Factors in Part I of this Annual Report.

Management and Professional Personnel. Due to our decentralized operating structure, significant decision-making authority resides with management at our operating companies, and our corporate management and professional and administrative personnel are relied upon to allocate capital and communicate, coordinate and help execute our business strategies. We are focused on our ability to attract and retain qualified employees for these important positions, as we rely on them to successfully manage our decentralized operations and grow and expand our business. We have also implemented enterprise-wide talent development and succession planning programs designed to identify and develop future and/or replacement candidates for key positions. For example, we have developed and administer a succession program with respect to our executive officers and other senior leadership personnel, which is reviewed and/or overseen by our Board of Directors (Board).

Compensation and Benefits

Our compensation programs are generally designed to align employee compensation with market practices and our performance, as well as provide the proper incentives to attract, retain and motivate employees. With respect to our executive officers, operating company management, other senior leadership and corporate employees, compensation programs consist of both fixed and variable components. The fixed portion is generally set based on consideration of various market factors, with variable compensation designed to reward employees based on company financial and operational performance. We also grant stock-based compensation broadly throughout our organization, including to management and key operations personnel at the majority of our operating companies, which we believe is a key component of our compensation programs that helps to align incentives throughout our decentralized organization. We also enter into employment agreements with our executive officers and certain other key personnel.

We provide additional benefits to our employees. For example, we provide health, welfare and benefit plans for most employees who are not covered by collective bargaining agreements, and we maintain a 401(k) plan pursuant to which eligible U.S. employees who are not provided retirement benefits through a collective bargaining agreement may make contributions through payroll deductions and to which we make certain matching contributions.

Ethics and Compliance

All of our employees are subject to Quanta’s Code of Conduct, which addresses compliance with applicable laws and Quanta’s policies concerning, among other things, general business ethics, competition, anti-corruption and bribery, environmental protection, conflicts of interest, harassment and discrimination, data security and privacy, and insider trading. Quanta’s Code of Conduct also informs employees and third parties (such as suppliers, subcontractors and members of the public) about the resources and confidential reporting mechanisms available to detect, prevent and report unethical and illegal conduct, and our Chief Compliance Officer communicates directly with our Board about actual and alleged violations of the law or the Code of Conduct. Training with respect to Quanta’s Code of Conduct and other policies and procedures is conducted as part of our comprehensive ethics and compliance training program.

Climate Change-Related Impacts

Our management considers climate-related risks and opportunities as part of its overall long-term strategic planning and enterprise risk management process, which are overseen by our Board. While the overall impact on our operations continues to evolve, various aspects of climate change, as well as market and societal concerns about the future impact of climate change, have resulted and are expected to continue to result in operational opportunities and challenges. These opportunities and

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challenges can arise from the physical risks associated with changes in climate, as well as technological advances, market developments and additional regulatory and compliance costs.

Changes in climate have caused, and are expected to continue to cause, among other things, changes to meteorological and hydrological patterns that in turn have impacted the frequency and intensity of wildfires, hurricanes, floods, droughts, winter storms and other storms and severe weather-related events and natural disasters. Our operating results can be significantly influenced by the climates in which we operate and severe weather events, and these changes have and could continue to significantly impact our future operating results. A greater amount of rainfall, snow, ice or other less accommodating weather conditions, including extreme heat, as well as an increase in severe weather events and natural disasters, reduces our productivity and causes delays and cancellations of our ongoing projects. However, an increase in certain of these events, such as hurricanes, tropical storms, wildfires, blizzards and ice storms, also creates opportunities for us to perform a greater amount of emergency restoration services and, as described above, can increase customer spending on modernization, grid hardening and other infrastructure improvements (e.g., fire hardening programs and storm hardening programs). The timing and impact of these events is difficult to predict and can vary from period to period, and our emergency restoration services attributable to these events can fluctuate significantly in any given year. Additionally, changes in climate could result in more accommodating weather patterns for greater periods of time in certain areas, which may enable us to increase our productivity in those areas.

Physical risks associated with changes in climate have also increased certain hazards associated with certain of our operations, which in turn has increased the potential for liability and increased the costs associated with such operations. For example, severe drought and high wind speeds have significantly increased the risk of wildfires throughout our operating locations, which in turn has exposed us and other contractors to increased risk of liability, particularly as these events can be started by electrical power and other infrastructure on which we have performed services. Given the potentially significant liabilities associated with these events, to the extent we are deemed liable or are otherwise responsible for damages or other amounts associated with a wildfire event, it could have a material adverse impact on our business. Furthermore, these climate conditions have also resulted in increased costs for wildfire-related third-party insurance and reduced the amount of insurance carriers are willing to make available to us under such policies.

Changes in climate have in the past, and may in the future, impact the markets in which we operate. For example, certain services within our Underground and Infrastructure segment, including large pipeline infrastructure services, have experienced periodic challenges as a result of concerns regarding the impact of fossil fuels or refined products on the environment. However, such concerns have recently lessened as a result of the overall increase in demand for electricity, which has in turn increased demand for our services and solutions associated with all forms of power generation, including legacy energy resources such as natural gas. Furthermore, in recent years, many utility customers have increased their renewable power generation portfolios (e.g., solar, wind, battery storage ) in part as a result of concerns associated with changes in climate, which has in turn increased demand for our services associated with renewable power generation and related electric power infrastructure.

Lastly, new legislation or regulation related to climate change could increase our costs. Most significantly, we maintain a large fleet of vehicles and a significant amount of construction machinery, and the costs associated with them could significantly increase as a result of regulations related to greenhouse gas emissions from such sources or regulations that result in an increase in fuel prices. Additionally, we may be subject to new rules relating to the disclosure of a range of climate-related risks. While certain of these rules are currently subject to litigation and the timing of implementation and finalization of such rules is uncertain, we are continuing to assess these rules and regulations and at this time we cannot predict the costs of implementation or any potential adverse impacts resulting from the rules. To the extent these rules are implemented, we or our customers could incur increased costs related to the assessment and disclosure of climate-related risks. In addition, enhanced climate disclosure requirements could accelerate the trend of certain stakeholders and lenders restricting or seeking more stringent conditions with respect to their investments in certain carbon intensive sectors, which could further impact our customers and demand for our services.

For additional information regarding the risks and opportunities described above, see Risks Related to Operating Our Business in Item 1A. Risk Factors in Part I of this Annual Report.

Risk Management and Insurance

We are insured for, among other things, employer’s liability, workers’ compensation, auto liability, aviation and general liability claims. We manage and maintain a portion of our risk through retentions and/or high deductibles, as well as, both directly and indirectly through our wholly-owned captive insurance company. The captive insurance company reimburses all claims up to the amount of the applicable deductible of any third-party insurance programs, as well as certain additional exposure related to the general and auto liability programs, which together, in certain circumstances, can be up to $70.0 million per occurrence. As a supplement to our high-deductible primary insurance and captive programs, we maintain insurance with excess insurance carriers for potential losses that exceed the amount of our deductible and captive insurance obligations. We

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renew our insurance policies on an annual basis, and therefore deductibles, captive insurance and/or reinsurance amounts, and levels of insurance coverage may change in future periods. For additional information regarding our insurance and the risks associated with insurance coverage, see Note 16 of the Notes to Consolidated Financial Statements in Item 8. Financial Statements and Supplementary Data and Risks Related to Operating Our Business in Item 1A. Risk Factors in Part I of this Annual Report.

Website Access and Other Information

Our website address is www.quantaservices.com. Interested parties may obtain free electronic copies of our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and any amendments to these reports in the Investors / SEC Filings section of our website or through the website of the SEC at www.sec.gov. These reports are available on our website as soon as reasonably practicable after we electronically file them with, or furnish them to, the SEC. We will also make available to any stockholder, without charge, copies of our Annual Report on Form 10-K as filed with the SEC. For copies of this or any other Quanta publication, stockholders may submit a request in writing to Quanta Services, Inc., Attn: Corporate Secretary, 2727 North Loop West, Houston, Texas 77008, or by phone at (713) 629-7600.

Investors and others should note that we announce material financial information and make other public disclosures of information regarding Quanta through SEC filings, press releases, public conference calls, and our website. We also utilize social media to communicate this information, and it is possible that the information we post on social media could be deemed material. Accordingly, we encourage investors, the media and others interested in our company to follow Quanta, and review the information we post, on the social media channels listed on our website in the Investors / Social Media section.

This Annual Report, our website and our social media channels contain information provided by other sources that we believe is reliable. We cannot provide assurance that the information obtained from other sources is accurate or complete. No information on our website or our social media channels is incorporated by reference herein.