NASDAQ: PLXS

•Discipline by Design – We hold ourselves accountable to delivering shareholder value through consistent application of a disciplined financial model.

Built on a foundation of innovation, we are relentless in our pursuit of excellence, aligning our team members, operations, systems of oversight and financial metrics to create a high performance, accountable organization with an engaged workforce deeply passionate about helping to create the products that build a better world.

Financial Model

Our primary long-term goal is to achieve a 9-12% compounded annual revenue growth rate while earning a return on invested capital ("ROIC") of 15%, which would significantly exceed our weighted average cost of capital ("WACC") and represent positive economic return. Economic return is the amount by which our ROIC exceeds our WACC, and we believe it is a fundamental driver of shareholder value. We review our internal calculation of WACC annually; for fiscal 2025, our WACC was 8.9%.

For more information regarding ROIC and economic return, which are non-GAAP financial measures, refer to "Management’s Discussion and Analysis of Financial Condition - Results of Operations - Return on Invested Capital ("ROIC") and economic return" in Part II, Item 7. For additional information on our use of non-GAAP financial measures, see Exhibit 99.1 to this annual report on Form 10-K, which exhibit is incorporated herein by reference.

Solutions

With integrated services throughout the product lifecycle, our team strives to create innovative and optimized solutions to deliver products to the market, keep products in the market longer and help manage the product lifecycle sustainably and responsibly.

•Design and Development – Using standard tools and processes throughout our six design centers worldwide, we leverage the latest technology and state-of-the-art design automation methodologies to provide comprehensive new product development and product commercialization solutions. The breadth of our capabilities across the product lifecycle enables us to integrate supply chain, manufacturing and service expertise into our designs, resulting in products developed with the full product lifecycle in mind.

•Supply Chain Solutions – Our supply chain experts engage in all of Plexus’ integrated solutions to identify opportunities for supply chain optimization. We offer services to help manage the full supply chain to minimize cost, mitigate risk and comply with trade regulations to provide a flexible, scalable and resilient solution for our customers.

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•New Product Introduction – When introducing a new product, we understand that time to market is critical to our customers. We have a dedicated team focused on decreasing time to market and transitioning products to full volume manufacturing, through a full suite of integrated new product introduction services, such as design for excellence, product lifecycle assessment, specialized design of test solutions and rapid prototyping.

•Manufacturing – Our approach to manufacturing focuses on innovation, continuous improvement and operational excellence. With a global footprint and scalable operations, we aim to tailor our manufacturing environment to meet each customer's needs worldwide. Our capabilities and our commitment to superior execution position us to support the complex technology and regulatory needs of the industries we serve, providing customers with dependable and flexible manufacturing solutions. We commit to exceptional quality and perfect delivery by standardizing, scaling and continuously improving, ensuring that the products we help create are reliable, safe and trusted in the moments that matter most. Quality Begins with Me is our promise to do the right thing, the first time, every time. We hold ourselves accountable for our customers, our team members and the world.

•Sustaining Services – We are committed to protecting our customers' brand reputation, supporting the success of each product in the market and extending a product's useful life through repair, refurbishment and related services. From influencing a product's design for serviceability, which creates early access for lifecycle extension services and repair, to aftermarket and end-of-life treatment, such as spare parts management, depot repair and part recovery services, we take a proactive and circular approach to service to help keep products in the market.

Through these integrated solutions, we proactively tackle tough challenges throughout the product lifecycle. We provide most of our solutions on a turnkey basis, under which we procure and warehouse all materials required for product assembly. We provide select solutions on a consignment basis, meaning our customers supply the necessary materials, while we provide the labor and other services required for product assembly. Other than certain test equipment, manufacturing equipment and software used for internal operations, we do not design or manufacture our own proprietary products.

Operations

Plexus is a Wisconsin-headquartered corporation operating from 26 active facilities, totaling approximately 5.0 million square feet. Our facilities are strategically located to support the design, manufacturing and service needs of customers' global supply chains in our targeted market sectors.

Customers and Market Sectors Served

We specialize in serving customers in the Aerospace/Defense, Healthcare/Life Sciences, and Industrial market sectors. Plexus serves a diverse customer landscape that includes industry-leading, branded product companies, along with other technology pioneering start-ups and emerging companies that may or may not maintain manufacturing capabilities. During fiscal 2025, we served approximately 190 customers. No customer accounted for over 10% of our sales in fiscal 2025 or 2024. Many of our large customers contract with us through multiple independent divisions, subsidiaries, production facilities or locations. We believe that in most cases our sales to any one such division, subsidiary, facility or location are independent of sales to others.

The distribution of our net sales by market sectors for the indicated fiscal years is shown in the following table:

Industry202520242023

Aerospace/Defense17%18%14%

Healthcare/Life Sciences40%39%44%

Industrial43%43%42%

Total net sales100%100%100%

Although our current business development focus is based on our targeted market sectors of Aerospace/Defense, Healthcare/Life Sciences, and Industrial, we evaluate our financial performance and allocate our resources geographically (see Note 11 "Reportable Segments, Geographic Information and Major Customers" in Notes to Consolidated Financial Statements regarding our reportable segments). Plexus offers an array of solutions for customers in each market sector and, aside from the specific go-to-market teams, generally we do not dedicate operational equipment, personnel or other resources to particular market sectors, nor do we internally track our costs and resources per market sector.

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Go-to-Market Strategy

Each market sector has a market sector vice president, as well as market sector senior director roles, who together oversee and provide leadership to business development and customer relationship management teams, supply chain, engineering, manufacturing and sustaining services subject matter experts and market sector specialists. These teams maintain expertise related to each market sector and execute sector strategies aligned to that market’s unique commercial delivery, quality and regulatory requirements.

Our market sector teams help to develop Plexus’ strategy for growth with a particular emphasis on expanding the value-add solutions we offer customers. Our sales and marketing efforts focus on expanding our engagements with existing customers as well as targeting new customers.

Materials and Suppliers

We typically purchase raw materials, including printed circuit boards and electronic components, from a wide variety of manufacturers and their authorized distributors. Under certain circumstances, we will purchase materials from independent distributors, customers or competitors. Many of these raw materials are unique to the designed assembly. By customer agreement, we purchase materials according to customer forecasts and purchase orders and supplier lead-times.

The key electronic raw materials we purchase include: advanced semiconductors, diodes, power management modules, microcontrollers, memory modules, interconnects, inductors, resistors, capacitors, power supplies and cable and wire. Volatile demand (in quantity or mix), material shortages, extended lead-times and subsequent allocations by our suppliers are an inherent risk within the electronics industry. We discuss the causes, implications, and potential implications of volatile demand and material shortages more fully in "Risk Factors" in Part I, Item 1A herein.

We also purchase non-electronic, typically custom engineered components such as molded/formed plastics, sheet metal fabrications, aluminum extrusions, robotics, motors, vision sensors, motion/actuation, fluidics, displays, die castings and various other hardware and fastener components. These materials are sourced from Plexus' preferred suppliers and customer directed suppliers. Altogether, purchased materials range from “off the shelf” to highly customized and vary widely in terms of market availability and price. Through our engineering product development engagements and through the quoting of new business, Plexus can influence the selection of new product materials, and therefore the selection of suppliers who outperform their peers.

Amidst a highly dynamic set of supply markets, Plexus' global supply chain management organization works to mitigate potential risks and ensure a steady flow of materials at competitive prices. We pursue these goals through supply chain solutions developed in collaboration with our customers and our suppliers, a commitment to strong supplier partnerships, use of proprietary risk management tools and aggressive management of supplier commitments.

Competition

Plexus operates in a highly competitive market, with a goal to be best-in-class at meeting the unique needs of our customers. A number of competitors may provide services similar to Plexus. Others may be more established in certain industry sectors, or have greater financial, manufacturing or marketing resources. Smaller competitors compete mainly in specific sectors and within limited geographic areas. Plexus also competes with in-house capabilities of current and potential customers. Plexus maintains awareness and knowledge of our competitors' capabilities in order to remain highly competitive within our target markets. Refer to the discussion in "Risk Factors" in Part I, Item 1A herein for further details on market competition.

We believe our ability to provide a full range of services that complement the entire product lifecycle across a global footprint provides a business advantage. Relative to our competition, overriding factors such as lower manufacturing volumes, production flexibility, unique fulfillment requirements and complex regulatory and quality requirements typically result in higher investments in inventory and selling and administrative costs for us. The cost variance from our competitors is especially evident relative to those that provide electronics manufacturing services for high-volume, less complex products, with less stringent requirements (e.g., consumer electronics).

Sustainability & Social Impact

We are committed to elevating the standards of business conduct through the adoption of sustainable and responsible business practices within our global operations. This commitment is made public through our membership with organizations such as the U.N. Global Compact ("UNGC"), including alignment to the U.N. Sustainable Development Goals and the Responsible Business Alliance ("RBA"). In service to our vision, we continue to evolve our solutions to better service our customers in light of changing market demands. This includes the opportunity we have to help deliver more sustainable and responsible products to the market. We continue to expand our product lifecycle capabilities in response to this heightened focus, as we seek to

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design more environmentally sustainable products, improve our production practices, assess and deploy product life extension and part recovery strategies, and enable a more sustainable, responsible supply chain for our customers.

We are focused on our own operational impact, as well, seeking to reduce our emissions, waste, water and use of natural resources, transition to renewable energy and reusable resources, and optimize our operations through adoption of new technologies and automation. Our commitment to reducing our environmental impact is captured in our Climate Policy, which helps to guide our objectives and offers structure to aid in prioritizing our efforts.

We are also focused on collaborating and integrating with our local communities and finding opportunities to partner throughout our value chain. Community involvement, volunteering and charitable giving are important to ensure we are investing and promoting positive impacts in the communities in which we operate and where our team members live. Within each community where we have a physical location, we provide donations to local charities that enhance innovation, promote technology-related educational programs (e.g., STEM) and improve the quality of life. Plexus also offers eight hours per year of paid, volunteer time off for team members who want to give back through community engagement events. In addition to local impacts realized through our team member volunteer efforts, the Plexus Community Foundation donated nearly $1.4 million in fiscal 2025, bringing its total giving to $12.4 million since 2004.

Refer to the discussion in "Risk Factors" in Part I, Item 1A herein for further details of environmental physical and transition risks, as well as the legal and regulatory landscape related to environmental matters, including climate change, that could adversely affect our business, results of operations, and financial condition.

Human Capital Management

People are the heart of who we are and what we do. How we engage and empower our team members is critical to how we deliver value and create sustained growth for our shareholders. We realize our success depends on the well-being and inclusive engagement of each individual on our team. As a responsible employer, we are committed to global standards of employment, which we effect through our Code of Conduct and Business Ethics ("Code of Conduct"), our Human Rights Policy and other labor and employment policies and through our commitment to the UNGC Sustainable Development Goals and the RBA. We also realize in order to attract and retain talented individuals we must provide our team members the ability to do meaningful work, personally and professionally develop, and create diverse and memorable experiences.

Purpose and Culture

We recognize a great culture is foundational to the success of our vision to help create the products that build a better world. We are proud of our culture and the recognition we have received over the years as a great place to work. In building a great culture, we embrace our five values:

•Growing our People – We foster a culture of trust, courage and growth, empowering each team member to realize their full potential.

•Building Belonging – We build an inclusive environment, valuing each team member, embracing diversity and promoting teamwork to achieve extraordinary outcomes together.

•Innovating Responsibly – We innovate and leverage technology, guided by a clear strategy, to boldly drive positive change and promote a sustainable future.

•Delivering Excellence – We commit to exceptional quality and perfect delivery by standardizing, scaling and continuously improving.

•Creating Customer Success – We exceed customer expectations and forge relationships built on trust, candor and shared successes.

Commitment to Our Values and Ethical Business Practices

Along with our values, we act in accordance with our Code of Conduct, which creates expectations and provides guidance for all team members, representatives and partners of Plexus to make the right decisions in conducting business. Our Code of Conduct includes topics such as corruption, discrimination, harassment, privacy, appropriate use of company assets, protecting confidential information and reporting Code of Conduct violations. Our Code of Conduct reinforces our passion for operating in a fair, honest, responsible and ethical manner and articulates our responsibilities as a trusted leader in the business community. The Code of Conduct also emphasizes the importance of having an inclusive, welcoming environment in which all team members feel empowered to do what is right and are expected to voice concerns should violations of the Code of Conduct be observed. All Plexus team members are required to complete training on the Code of Conduct biennially.

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Human Rights

At the core of our value system is a fundamental respect for human rights. Our Human Rights Policy formalizes Plexus' commitment to respect human rights and embodies internationally-recognized principles and the laws of the countries in which we operate.

We prohibit discrimination and harassment, recruiting fees imposed on our workers, the use of child labor, forced labor or labor that results from human trafficking, and the unreasonable restriction of movement or travel of workers. We support reasonable working hours and time off, fair wages, access to basic liberties (including clean sanitation facilities and potable water), freedom of association, the humane treatment of all workers and fair and honest business practices. Our Human Rights Policy supports the RBA Code of Conduct labor standards framework, and reinforces our statement in support of the California Transparency in Supply Chains Act and the UK Modern Slavery Act.

Talent Development & Acquisition

People are the heart of who we are and what we do. We create, implement and accelerate development opportunities for our team members in order to enable business growth, enhance our culture, drive leadership accountability and inspire purposeful engagement. Our commitment to holistic talent management means that we expect and reward high performance and address underperformance with urgency, candor and empathy. We engage in regular talent reviews to calibrate on the performance and potential of our teammates, development opportunities, career pathing and the strength of our succession plans. During these reviews, we also review retention rates and the talent of our leaders and leadership pipeline. Competency-based training, leadership development programs and online learning promote a learning culture and provide ongoing development for team members at all levels. We also have established a formal mentoring program that aids in the development and retention of talent. While our goal is to develop our own talent, we are equally committed to recruiting new graduate and experienced talent who bring transferable experiences and skillsets.

Our Culture of Belonging

Our history of doing the right thing is deeply rooted in our values and woven into everything we do. That means we foster an inclusive environment that builds a sense of belonging, where every team member is valued for their unique contributions and empowered to realize their full potential. By embracing inclusion and promoting teamwork, we achieve extraordinary outcomes together.

•Employee Engagement – At every facility, in every region and at all levels, we strive to continuously improve the engagement of our team members. We poll team members regularly through our employee engagement survey and we identify strengths and act on areas of opportunity to enhance our work environment and increase employee satisfaction.

•Executive and Board Oversight – To oversee strategic objectives and to ensure appropriate accountabilities exist to support our efforts, how we build belonging is incorporated into our executive Sustainable & Responsible Business Practices Committee, made up of key members of executive management, including our Chief Executive Officer. In addition, the Compensation and Leadership Development Committee of our Board of Directors reviews our human capital management strategy, including progress to cultivate an optimized workforce and inclusive culture.

•Employee Resource Groups – Our ERGs are voluntary, employee-driven, executive-sponsored groups organized around common interests and legitimate business purposes. Plexus' current ERGs include Plexus Pride, Plexus Veterans Network, Plexus Women in Network, Plexus Young Professionals and UnusPlexus.

Employee Benefits & Programs

Plexus has a number of policies and benefits in place to support the unique needs and overall well-being of our team members and their families, including competitive health and welfare plans, a flexible workplace, paid parental leave and a Plexus wellness program to ensure our team members have access to the resources they need to lead healthy, balanced lives. For many of our locations, this includes access to our Employee Assistance Program ("EAP") - or similar program depending on the country of employment - that provides confidential support for stress management and mental health, including counseling and resources for team members and their households.

Compensation

We employ a "pay for performance" approach, emphasizing a direct correlation between performance and rewards. Leaders are provided with the flexibility to recognize exceptional individual contributions through customized elements of pay such as base salary, cash incentives and equity (company stock) compensation. Short and long-term incentive pay is designed to be competitive, improve employee retention, reward team members for performance supporting our strategic objectives and align team members with the interests of shareholders to deliver both short-term and long-term results.

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Our compensation guidelines and pay structures are adapted to reflect market dynamics and currency exchange rate fluctuations, ensuring alignment with regional trends, pay range segments and applicable experience. A risk assessment on our compensation plans and strategy is performed annually, including a market pay analysis to ensure we are competitive with local market practices where we operate. We provide the results of this risk assessment and a summary of all global total rewards programs to the Compensation and Leadership Development Committee of our Board of Directors on an annual basis. These practices not only facilitate a clear and transparent understanding of our compensation philosophy among team members but also ensure internal fairness and external market competitiveness.

Worker Health and Safety

Protecting our team and those within our communities is paramount as we strive to be the safest place for our team members outside of their homes. We are committed to complying with applicable laws and taking a proactive approach to ensure we conduct all of our operations across the globe safely and responsibly. We maintain a method of evaluating environmental, health and safety ("EHS") performance for continual improvement and we are committed to providing a workplace that promotes the health and safety of all who walk through our doors.

Our Corporate Policy for Quality, Environmental, Health & Safety and Social Responsibility Management sets forth our EHS policy statement, which includes our commitment to: maintain, evaluate and continuously improve our global EHS management system; provide processes for consultation and participation of team members to reduce safety risks; and maintain compliance with applicable environmental and occupational health and safety laws and other requirements. These requirements are related to topics such as: monitoring, tracking and reporting of air and water emissions; tracking and disposing of wastes generated from our manufacturing process; and evaluating and mitigating employee health and safety risks in our facilities.

Seventeen of our 18 manufacturing facilities are certified to ISO 14001 Environmental Management and three of 18 are certified to ISO 45001 Occupational Health and Safety Management standards. All of our manufacturing facilities, regardless of formal certification, abide by global policies and processes that align with both of these standards. Two of our 18 facilities are certified to the ISO 50001 Energy Management system, which requires the development and implementation of a comprehensive energy management system that helps the site achieve continual improvement of energy performance, including efficiency, security, use and consumption.

Our site teams are trained on these requirements and certifications to these standards are audited and renewed annually in alignment with ISO standards. Further, we provide education and training for every team member on important environmental and safety topics applicable to their role, leveraging a risk-based approach to training to ensure our team members have the knowledge they need to keep themselves and their peers safe and the environment healthy. To help drive best practices and enhance our environmental and safety performance, we employ a global team of over 50 EHS professionals who help to develop and deploy standard policies and procedures to protect our team members and to enable safe and sustainable operations.

Human Capital Management Governance

Our Chief Human Resources Officer ("CHRO") directs our human capital management strategy and provides an update to the Compensation and Leadership Development Committee of our Board of Directors quarterly. This update may include, among other topics, talent attraction, development and retention; succession planning, including successor candidates for key management roles; corporate culture; employee engagement; compensation practices; training; and progress to advance initiatives. Management also updates the Board of Directors regularly on employee-related policies, trends and efforts intended to protect our team members and to preserve our corporate culture, such as those related to EHS and Ethics Hotline reporting.

Employee Data

Of our over 20,000 team members, 49.5% are female, 50.4% are male and 0.1% choose not to identify. The majority of our workforce, 58.3%, is located in our APAC region, while 30.1% and 11.6% of our team members are located in our AMER and EMEA regions, respectively. Approximately 211 of our team members in the United Kingdom are covered by union agreements. These union agreements are typically renewed at the beginning of each year, although in a few cases these agreements may last two or more years. Our global team members outside the United Kingdom are not covered by union or collective bargaining agreements. We have no history of labor disputes at any of our facilities, and we believe that our employee relationships are positive and stable. Given the quick response times required by our customers, we seek to maintain flexibility to scale our operations as necessary to maximize efficiency. To do so, we use skilled temporary labor in addition to our full-time employees.

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Intellectual Property

We own various service marks that we use in our business, which are registered in the trademark offices of the United States and other countries. We develop and maintain trade secrets but do not generally seek to patent inventions. We hold multiple copyrights including the copyright on www.plexus.com.

Information Technology

Our core solutions for manufacturing facilities include a single-instance enterprise resource planning (“ERP”) system in addition to product data management and advanced planning and scheduling systems, along with consistent solutions for warehouse management and manufacturing execution that support our global operations. This consistency augments our other management information systems, allowing us to standardize the translation of data from multiple production facilities into operational and financial information required by the business. The related software licenses are of a general commercial character on terms customary for these types of agreements.

In addition to our core solutions, we are committed to investing in new platform technologies, such as advanced manufacturing execution systems, process automation, warehouse automation, artificial intelligence, real-time vision and anomaly detection systems and collaboration tools. These investments are aimed at enhancing productivity, optimizing operational efficiency, and driving differentiation in a competitive landscape. Refer to the discussion in "Cybersecurity" in Part I, Item 1C herein for details on our cybersecurity risk management strategy and governance.

Compliance with Laws and Regulations

As a global public company that designs, manufactures and services highly complex products in demanding regulatory environments, our operations are subject to a variety of laws, regulations and compliance obligations. We strive to implement robust internal controls, quality management systems and management systems of compliance that govern our internal actions and mitigate our risk of non-compliance. We also make efforts to identify non-compliance concerns through internal and external audits, risk assessments as well as an ethics hotline reporting system. Plexus is also committed to supporting product safety and environmental compliance regulations as may be required by our customers. This support may include customized operational processes or collecting data or compliance information on parts or production materials to meet certain laws, regulations or end market requirements, such as the Restrictions on Hazardous Substances ("RoHS") 2011/65/EU, Waste Electrical and Electronic Equipment ("WEEE") 2012/19/EU directives and Registration, Evaluation, Authorization and restriction of Chemicals ("REACH") EC 1907/2006 EU directive.

Regulatory Requirements

All Plexus manufacturing and engineering facilities are certified to a baseline Quality Management System standard per ISO9001:2015. We have capabilities to assemble finished medical devices meeting the U.S. Food and Drug Administration’s (“FDA”) Quality Systems Regulation requirements and similar regulatory requirements in other countries.

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We have additional certifications and/or registrations held by certain facilities in the following regions:

AMERAPACEMEA

Medical Standard ISO 13485:2016XXX

21 CFR Part 820 (FDA) (Finished Medical)XXX

JGMP accreditationXXX

GMP-Korea certificationXXX

ANVISA accreditationX

NPMA (National Medical Products Administration) registrationX

ISO 14001(environmental management)XXX

ISO 45001 (occupational health and safety)X

ANSI/ESD (Electrostatic Discharge Control Program) S20.20XX

ITAR (International Traffic and Arms Regulation) self-declarationX

Aerospace Standard AS9100XXX

NADCAP certificationXXX

FAR 145 certification (FAA repair station)X

EASA repair approvalX

ATEX/IECEx certificationX

IRIS certification (Railway)X

ISO 50001:2011 (energy management)X

Bureau of Indian Standards (BIS)X

TL9000 (telecommunications)X

Refer to the discussion in "Risk Factors" in Part I, Item 1A herein for further details on legal and regulatory obligations that could adversely affect our business, results of operation and financial conditions.

Additional Information

Our global headquarters is located at One Plexus Way, Neenah, Wisconsin, 54956. Plexus maintains a website at www.plexus.com. As soon as is reasonably practical, after we electronically file or furnish all reports to the Securities and Exchange Commission ("SEC"), we provide online copies of such reports, free of charge. These reports include: Proxy Statements, Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, Specialized Disclosure Reports on Form SD and amendments to those reports. These reports are also accessible at the SEC's website at www.sec.gov. Our Code of Conduct is also posted on our website. You may access these SEC reports and the Code of Conduct by following the links under "Investors" at our website.

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