WESCO International : Q1 2024 Marketing Deck_Final

Wesco International

Investor Overview

March 2024

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Forward-Looking Statements

All statements made herein that are not historical facts should be considered as "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements involve known and unknown risks, uncertainties and other factors that may cause actual results to differ materially. These statements include, but are not limited to, statements regarding business strategy, growth strategy, competitive strengths, productivity and profitability enhancement, competition, new product and service introductions and liquidity and capital resources, as well as statements regarding the expected benefits and costs of the transaction between Wesco and Anixter International Inc., including anticipated future financial and operating results, synergies, accretion and growth rates, and the combined company's plans, objectives and expectations.. Such statements can generally be identified by the use of words such as "anticipate," "plan," "believe," "estimate," "intend," "expect," "project," and similar words, phrases or expressions or future or conditional verbs such as "could," "may," "should," "will," and "would," although not all forward-looking statements contain such words. These forward-looking statements are based on current expectations and beliefs of Wesco's management, as well as assumptions made by, and information currently available to, Wesco's management, current market trends and market conditions and involve risks and uncertainties, many of which are outside of Wesco's and Wesco's management's control, and which may cause actual results to differ materially from those contained in forward-looking statements. Accordingly, you should not place undue reliance on such statements.

Important factors that could cause actual results or events to differ materially from those presented or implied in the forward-looking statements include, among others, the failure to achieve the expected benefits

of the transaction between Wesco and Anixter or the anticipated benefits of Wesco's acquisition of Rahi Systems Holdings, Inc., in the expected timeframe or at all, unexpected costs or problems that may arise in

successfully integrating the businesses of the companies, the impact of increased interest rates or borrowing costs, failure to adequately protect Wesco's intellectual property or successfully defend against infringement claims, failure to execute Wesco's environmental, social and governance (ESG) programs as planned; disruption of information technology systems or operations, natural disasters (including as a result of climate change), health epidemics, pandemics and other outbreaks (such as the ongoing COVID-19 pandemic, including any resurgences or new variants), supply chain disruptions, geopolitical issues, including the impact of the evolving conflicts in the Middle East and Ukraine, the impact of sanctions imposed on, or other actions taken by the U.S. or other countries against, Russia or China, the increased risk of cyber incidents and exacerbation of key materials shortages, inflationary cost pressures, material cost increases, demand volatility, and logistics and capacity constraints, which may have a material adverse effect on the combined company's business, results of operations and financial condition. All such factors are difficult to predict and are beyond the company's control. Additional factors that could cause results to differ materially from those described above can be found in Wesco's Annual Report on Form 10-K for the fiscal year ended December 31, 2023 and Wesco's other reports filed with the U.S. Securities and Exchange Commission.

Non-GAAP Measures

In addition to the results provided in accordance with U.S. Generally Accepted Accounting Principles ("U.S. GAAP"), this presentation includes certain non-GAAP financial measures. These financial measures include organic sales growth, gross profit, gross margin, earnings before interest, taxes, depreciation and amortization (EBITDA), adjusted EBITDA, adjusted EBITDA margin, financial leverage, free cash flow, adjusted selling, general and administrative ("SG&A") expenses, adjusted income from operations, adjusted operating margin, adjusted provision for income taxes, adjusted income before income taxes, adjusted net income, adjusted net income attributable to Wesco International, Inc., adjusted net income attributable to common stockholders, and adjusted earnings per diluted share. The Company believes that these non-GAAP measures are useful to investors as they provide a better understanding of our financial condition and results of operations on a comparable basis. Additionally, certain non-GAAP measures either focus on or exclude items impacting comparability of results such as merger-related and integration costs, and the related income tax effect of such items, allowing investors to more easily compare the Company's financial performance from period to period. Management does not use these non-GAAP financial measures for any purpose other than the reasons stated above.

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Transformational Combination of Wesco + Anixter

5.0% 5.1%

~17% Adjusted EBITDA CAGR

2019 - 2023

Delivering superior financial results

1 Adjusted EBITDA is defined as EBITDA before other non-operating expenses (income), non-cashstock-based compensation, and merger-related and integration costs. See Appendix for non-GAAP reconciliations.

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2024 outlook: reported sales growth 1% - 4% and free cash flow $600 - $800 million

1. Not adjusted for differences in foreign exchange rates
2. $900 million of 6.375% senior notes due 2029 and $850 million of 6.625% senior notes due 2032
3. Organic sales on a workday adjusted basis; 2024 are preliminary sales per workday results not adjusted for differences in foreign exchange rates

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Secular Trends + Share Growth Leads to Market Outperformance

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Our Digital Transformation

Innovating Across Our Entire Technology Landscape

Big Data

Data Office

Digitally transforming our company

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Annual Value Creation Framework

Virtuous cycle of value creation for Wesco

1 Adjusted EBITDA is defined as EBITDA before other non-operating expenses (income), non-cashstock-based compensation, and merger-related and integration costs.

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Why Invest in Wesco

• Fortune 200 B2B Supply Chain Solutions Leader
• • Global capabilities and leading scale
  • Higher growth and higher margin end-markets
  • Cross-sellcombined with attractive long-term secular growth trends
• Strategy Delivers Above-Market Growth
• • Share gains
  • Margin expansion
  • Double-digitprofit growth
• Increased Cash Generation and Enterprise Value Creation
• • Investments in digitalization to accelerate gains
  • Increasing return of capital to shareholders (buyback plus dividend)
  • Expanding balance sheet capacity supports M&A ambitions

Focused on delivering superior results and

achieving a premium multiple

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