NYSE: PWR

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:

l American Electric Power Company, Inc. l National Grid plc

l CenterPoint Energy, Inc. l NextEra Energy, Inc.

l Comcast Corporation l NiSource, Inc.

l Duke Energy Corporation l Pattern Energy

l
Engie IR Holdings LLC
l PG&E Corporation

l Entergy Corporation l Puget Sound Energy, Inc.

l Exelon Corporation l
RWE AG

l FirstEnergy Corp. l
Santos Limited

l Hydro One Incorporated l Sempra Energy

l Iberdrola Group l The Southern Company

l Idaho Power Company l The Williams Companies, Inc.

l Invenergy LLC l Turner Construction Company

l Lower Colorado River Authority l Xcel Energy Inc.

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.

Year Ended December 31,

2025 2024 2023

Utility and Power
70 % 74 % 75 %

Energy and Other
17 17 19

Technology, Manufacturing and Communications
13 9 6

Total revenues 100 % 100 % 100 %

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