WillScot Mobile Mini : WSC Q1 2024 Earnings Presentation

May 2, 2024

Quarterly Investor Presentation

First Quarter 2024

Safe Harbor

Forward Looking Statements

This presentation contains forward-looking statements (including the guidance/outlook contained herein) within the meaning of the U.S. Private Securities Litigation Reform Act of 1995 and Section 21E of the Securities Exchange Act of 1934, as amended. The words "estimates," "expects," "anticipates," "believes," "forecasts," "plans," "intends," "may," "will," "should," "shall," "outlook," "guidance," "see," "have confidence" and variations of these words and similar expressions identify forward-looking statements, which are generally not historical in nature. Certain of these forward-looking statements include statements relating to: our mergers and acquisitions pipeline, acceleration of our run rate, acceleration toward and the timing of our achievement of our three to five year milestones, growth and acceleration of cash flow, driving higher returns on invested capital, and Adjusted EBITDA margin expansion, as well as statements involving the proposed acquisition of McGrath (the "Proposed Transaction"), including anticipated time of closing, the expected scale, operating efficiency and synergies, stockholder, employee and customer benefits, the amount and timing of revenue and expense synergies, future financial benefits and operating results, expectations relating to the combined customer base and rental fleet, and tax treatment for the acquisition. Forward-looking statements are subject to a number of risks, uncertainties, assumptions and other important factors, many of which are outside our control, which could cause actual results or outcomes to differ materially from those discussed in the forward-looking statements. Certain of these forward-looking statements relate to the proposed transaction, including: expected scale; operating efficiency; stockholder, employee and customer benefits; key assumptions; timing of closing; the amount and timing of revenue and expense synergies; future financial benefits and operating results; and integration spend. Although the Company believes that these forward-looking statements are based on reasonable assumptions, they are predictions and we can give no assurance that any such forward-looking statement will materialize. Important factors that may affect actual results or outcomes include, among others, our ability to acquire and integrate new assets and operations; our ability to judge the demand outlook; our ability to achieve planned synergies related to acquisitions; regulatory approvals; our ability to successfully execute our growth strategy, manage growth and execute our business plan; our estimates of the size of the markets for our products; the rate and degree of market acceptance of our products; the success of other competing modular space and portable storage solutions that exist or may become available; rising costs and inflationary pressures adversely affecting our profitability; potential litigation involving our Company; general economic and market conditions impacting demand for our products and services and our ability to benefit from an inflationary environment; our ability to maintain an effective system of internal controls; and such other risks and uncertainties described in the periodic reports we file with the SEC from time to time (including our Form 10-K for the year ended December 31, 2023), which are available through the SEC's EDGAR system at www.sec.gov and on our website. Any forward-looking statement speaks only at the date on which it is made, and the Company disclaims any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

Non-GAAP Financial Measures

This presentation includes non-GAAP financial measures, including Adjusted EBITDA, Adjusted EBITDA Margin from continuing operations, Free Cash Flow, Free Cash Flow Margin, Return on Invested Capital, Net CAPEX and Net Debt to Adjusted EBITDA ratio. Adjusted EBITDA is defined as net income (loss) plus net interest (income) expense, income tax expense (benefit), depreciation and amortization adjusted to exclude certain non-cash items and the effect of what we consider transactions or events not related to our core business operations, including net currency gains and losses, goodwill and other impairment charges, restructuring costs, costs to integrate acquired companies, costs incurred related to transactions, non-cash charges for stock compensation plans, gains and losses resulting from changes in fair value and extinguishment of common stock warrant liabilities, and other discrete expenses. Adjusted EBITDA Margin from continuing operations is defined as Adjusted EBITDA divided by revenue. Free Cash Flow is defined as net cash provided by operating activities, less purchases of, and proceeds from, rental equipment and property, plant and equipment, which are all included in cash flows from investing activities. Free Cash Flow Margin is defined as Free Cash Flow divided by revenue. Return on Invested Capital is defined as adjusted earnings before interest and amortization divided by average invested capital. Adjusted earnings before interest and amortization is the sum of income (loss) before income tax expense, net interest (income) expense, amortization adjusted for non-cash items considered non-core to business operations including net currency (gains) losses, goodwill and other impairment charges, restructuring costs, costs to integrate acquired companies, non-cash charges for stock compensation plans, gains and losses resulting from changes in fair value and extinguishment of common stock warrant liabilities, and other discrete expenses, reduced by our estimated statutory tax rate. Given we are not a significant US taxpayer due to our current tax attributes, we include estimated taxes at our current statutory tax rate of approximately 26%. Net assets is total assets less goodwill and intangible assets, net and all non- interest bearing liabilities and is calculated as a five quarter average. Net CAPEX is defined as purchases of rental equipment and refurbishments and purchases of property, plant and equipment (collectively, "Total Capital Expenditures"), less proceeds from the sale of rental equipment and proceeds from the sale of property, plant and equipment (collectively, "Total Proceeds"), which are all included in cash flows from investing activities. Net Debt to Adjusted EBITDA ratio is defined as Net Debt divided by Adjusted EBITDA. The Company believes that Adjusted EBITDA and Adjusted EBITDA margin are useful to investors because they (i) allow investors to compare performance over various reporting periods on a consistent basis by removing from operating results the impact of items that do not reflect core operating performance; (ii) are used by our board of directors and management to assess our performance; (iii) may, subject to the limitations described below, enable investors to compare the performance of the Company to its competitors; (iv) provide additional tools for investors to use in evaluating ongoing operating results and trends; and (v) align with definitions in our credit agreement. The Company believes that Free Cash Flow and Free Cash Flow Margin are useful to investors because they allow investors to compare cash generation performance over various reporting periods and against peers. The Company believes that Return on Invested Capital provides information about the long-term health and profitability of the business relative to the Company's cost of capital. The Company believes that the presentation of Net CAPEX provides useful information to investors regarding the net capital invested into our rental fleet and plant, property and equipment each year to assist in analyzing the performance of our business. Adjusted EBITDA is not a measure of financial performance or liquidity under GAAP and, accordingly, should not be considered as an alternative to net income or cash flow from operating activities as an indicator of operating performance or liquidity. These non-GAAP measures should not be considered in isolation from, or as an alternative to, financial measures determined in accordance with GAAP. Other companies may calculate Adjusted EBITDA and other non-GAAP financial measures differently, and therefore the Company's non-GAAP financial measures may not be directly comparable to similarly-titled measures of other companies. For reconciliations of the non-GAAP measures used in this presentation (except as explained below), see "Reconciliation of Non-GAAP Financial Measures" included in this presentation.

Information regarding the most comparable GAAP financial measures and reconciling forward-looking Adjusted EBITDA, Net CAPEX, and Free Cash Flow to those GAAP financial measures is unavailable to the Company without unreasonable effort. We cannot provide the most comparable GAAP financial measures nor reconciliations of forward-looking Adjusted EBITDA, Net CAPEX, and Free Cash Flow to GAAP financial measures because certain items required for such reconciliations are outside of our control and/or cannot be reasonably predicted, such as the provision for income taxes. Preparation of such reconciliations would require a forward-looking balance sheet, statement of income and statement of cash flow, prepared in accordance with GAAP, and such forward-looking financial statements are unavailable to the Company without unreasonable effort. Although we provide ranges of Adjusted EBITDA and Net CAPEX that we believe will be achieved, we cannot accurately predict all the components of the Adjusted EBITDA and Net CAPEX calculations. The Company provides Adjusted EBITDA and Net CAPEX guidance because we believe that Adjusted EBITDA and Net CAPEX, when viewed with our results under GAAP, provides useful information for the reasons noted above.

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Safe Harbor

Recent Developments

Entry into an Agreement to Acquire McGrath RentCorp

On January 28, 2024, the Company, along with its newly formed subsidiaries, Brunello Merger Sub I, Inc. ("Merger Sub I") and Brunello Merger Sub II, LLC ("Merger Sub II"), entered into an Agreement and Plan of Merger (the "Merger Agreement") with McGrath RentCorp ("McGrath"). Merger Sub I will merge with and into McGrath (the "First-Step Merger"), with McGrath surviving the First-Step Merger and, immediately thereafter, McGrath will merge with and into Merger Sub II (the "Second-Step Merger" and together with the First-Step Merger, the "McGrath Acquisition"), with Merger Sub II surviving the Second-Step Merger as a wholly owned subsidiary of the Company. At the effective time of the First-Step Merger, and subject to the terms and subject to the conditions set forth in the Merger Agreement, each outstanding share of the common stock of McGrath shall be converted into the right to receive either (i) $123.00 in cash or (ii) 2.8211 shares of validly issued, fully paid and nonassessable shares of the Company's common stock. McGrath shareholders will receive for each of their shares either $123.00 in cash or 2.8211 shares of WillScot Mobile Mini common stock, as determined pursuant to the election and allocation procedures in the merger agreement under which 60% of McGrath's outstanding shares will be converted into the cash consideration and 40% of McGrath's outstanding shares will be converted into the stock consideration. Under the terms of the Merger Agreement, we expect McGrath's shareholders would own approximately 12.6% of the Company following the McGrath Acquisition.

The McGrath Acquisition has been approved by the respective boards of directors of the Company and McGrath. The McGrath Acquisition is subject to customary closing conditions, including receipt of regulatory approval and approval by McGrath's shareholders, and is expected to close in 2024.

In connection with the Merger Agreement, the Company entered into a commitment letter on January 28, 2024, which was further amended and restated on February 12, 2024 (the "Commitment Letter"), pursuant to which certain financial institutions have committed to make available to Williams Scotsman, Inc. (WSI), in accordance with the terms of the Commitment Letter, (i) a $500 million eight year senior secured bridge credit facility, (ii) a $500 million five year senior secured bridge credit facility and (iii) an upsize to WSI's existing $3.7 billion ABL Facility by

$750 million to $4.5 billion to repay McGrath's existing credit facilities and notes, fund the cash portion of the consideration, and pay the fees, costs and expenses incurred in connection with the McGrath Acquisition and the related transactions, subject to customary conditions.

Important Information About the Proposed Transaction

In connection with the Proposed Transaction, the Company filed a registration statement on Form S-4 (No. 333- 278544), which includes a preliminary prospectus of the Company and a preliminary proxy statement of McGrath (the "proxy statement/prospectus"), and each party will file other documents regarding the Proposed Transaction with the SEC. No offering of securities shall be made, except by means of a prospectus meeting the requirements of Section 10 of the U.S. Securities Act of 1933, as amended. INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE PROXY STATEMENT/PROSPECTUS AND OTHER RELEVANT DOCUMENTS FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY, IF AND WHEN THEY BECOME AVAILABLE, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION THAT STOCKHOLDERS SHOULD CONSIDER BEFORE MAKING ANY DECISION REGARDING THE PROPOSED TRANSACTION. A definitive proxy statement/prospectus will be sent to McGrath's stockholders. Investors and security holders will be able to obtain these documents (if and when available) free of charge from the SEC's website at www.sec.gov. The documents filed by the Company with the SEC may also be obtained free of charge from the Company by requesting them by mail at WillScot Mobile Mini Holdings Corp., 4646 E. Van Buren Street, Suite 400, Phoenix, Arizona 85008. The documents filed by McGrath may also be obtained free of charge from McGrath by requesting them by mail at McGrath RentCorp, 5700 Las Positas Road, Livermore, California 94551 Attn: Investor Relations.

Participants in the Solicitation

The Company, McGrath, their respective directors and executive officers and other members of management and employees and certain of their respective significant stockholders may be deemed to be participants in the solicitation of proxies in respect of the Proposed Transaction. Information about the Company's directors and executive officers is available in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2023, which was filed with the SEC on February 20, 2024. Information about McGrath's directors and executive officers is available in McGrath's Amendment No. 1 to Annual Report on Form 10-K/A for the fiscal year ended December 31, 2023, which was filed with the SEC on April 16, 2024. Information regarding the persons who may, under the rules of the SEC, be deemed participants in the proxy solicitation and a description of their direct and indirect interests, by security holding or otherwise, will be contained in the proxy statement/prospectus and other relevant materials to be filed with the SEC regarding the Proposed Transaction when they become available. Investors should read the proxy statement/prospectus carefully when it becomes available before making any voting or investment decisions. You may obtain free copies of these documents from the SEC, the Company or McGrath as indicated above.

No Offer or Solicitation

This presentation shall not constitute an offer to sell or the solicitation of an offer to buy any securities, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offering of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended.

Additional Information and Where to Find It

Additional information can be found on the company's website at www.willscotmobilemini.com.

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Table of Contents

5 WillScot Mobile Mini Business Overview

20 WillScot Mobile Mini to Acquire McGrath

29 Q1 2024 Operating Results

32 Q1 2024 Financial Review

39 Value Drivers

43 Appendix

4

The Continuous Evolution of Turnkey Spaces

Leading Onsite Comfort & Facilities

From restrooms to efficient climate control, we aim to make your site as comfortable and productive as possible.

Climate-Controlled Storage

Seamlessly manage temperature sensitive goods and materials across diverse industries, applications, and infrastructures.

Clearspan Structures

Expansive, durable, and highly configurable structures that can be rapidly deployed and meet a vast array of needs from warehousing to aerospace.

Unmatched Logistics

Ability to deploy solutions when and where our customers need them - anywhere in North America - and then remove everything as though we were never there.

Turnkey Space Solutions

Multiple options and configurations, combined with essentials such as furniture, fixtures, steps, restrooms, coverage, and more, can make your workspace functional right away.

Turnkey Storage Solutions

Highly customized storage solutions to help you maximize your space and keep your valuable items secure.

5

WSC has an established formula to drive sustainable growth and returns

1	Clear Market Leadership
2	Compelling Unit Economics And Return on Invested Capital
3	Predictable Recurring Lease Revenues
4	Diversified Customer Segments And Flexible Go-To-Market

#1	In >$15B North American market for flexible space solutions
>25%	Unlevered IRRs on portable storage and turnkey modular space
fleet investments
17%	Return on Invested Capital over LTM with >1,000 bps expansion
since 2019
~3 year	Average lease duration reduces volatility
>95%	Of revenue is from recurring leasing and services revenue
<15%	Of revenue is from our top-50 customers

15 Discrete customer segments levered to U.S. GDP with ability to reposition for infrastructure and shifting sector demand

5	Powerful $1B Organic Revenue Growth Levers
6	Proven Platform For Accretive M&A
7	Scalable Technology Enabling Efficiencies
8	Robust Free Cash Flow Driving Value Creation

~$500M

>10%

>80%

~$5B

>1,400 bps

26%

$3.24 3.3x 6.4%

Revenue growth opportunity from high margin VAPS1

Y/Y modular space and portable storage rate growth, inclusive of

VAPS, for 26 quarters and 9 quarters, respectively

Customer segment overlap and 40% customer overlap between modular and storage supports cross-selling

Acquired enterprise value through 30+ transactions in 7 years

Adjusted EBITDA Margin expansion since 2017

FCF Margin in LTM inside medium term range of 20% - 30%

FCF per share in LTM growing to $4.00+ within 3 years2 Leverage inside target range of 3.0x to 3.5x3

Reduction in share count in LTM 3

1 Value-Added Products

2 Calculated using Free Cash Flow over the last 12 months and common stock outstanding of 190,598,309 shares as of March 31, 20246 3 As of 3/31/2024

We offer the most flexible and cost-effective temporary space and storage solutions

132 FLEX units in use during an Olympic stadium project in Montreal.

WillScot supports repairs at the Statue of Liberty…

WSC modular facilities utilized in the construction of the Palo Alto Public Safety building.

VAPS inside a storage container enable our customers to start their projects immediately and safely.

…and at the United States Capitol building.

7

Our scale is a key competitive advantage and value driver for our customers

Phoenix, AZ

Headquarters Branch

Alaska

Hawaii

• We leverage our scale to win locally
• ~132M+ square feet of turnkey space relocatable anywhere in North America
• Sophisticated commercial and operational technology platform
• ~5,000 experts safely work ~10M hours annually
• ~820 trucks owned safely drive ~101k miles daily
• ~363K units deployed over 20 to 30-year useful lives
• 20k+ units refurbished or reconfigured annually
• 85k+ customers
• No customer >2% of revenue

8

Our business is inherently sustainable and a pioneer within the industrial circular economy

Alternatives

Permanent new construction

Requires extensive materials and resources to construct, with disposal of the structure upon project completion

Temporary space solutions

Provide basic space on the project site, and all units will be reused for future efforts

Our circular economy solutions Our current solutions

Ready to Work solution

Incorporates VAPS to drive reuse of more products and equipment, in addition to the units

Future value proposition

• We have implemented circular economy practices for decades.
• Our space solutions, accompanied by VAPS, are designed to be reused, relocated, reconfigured, and refurbished.

Subleased offsite workspace

Increases transportation and risk due to travel between project site and workspace

Refurbishment process

Circular by design, our lease-and-renew business model helps our customers achieve their ESG goals by reducing material usage, emissions, and costs.

Turnkey logistics solution

Immediate opportunity to improve route efficiencies while transitioning to clean energy solutions by delivering/picking up the units with an alternative fuel vehicle (EV, CNG) and powering the unit with solar energy

• Circular by design, our lease-and-renew business model helps our customers achieve their ESG goals by reducing material and labor usage, emissions, and costs.

9

We serve diverse customer segments and have the ability to reposition within them

Revenue By Customer Segment1

Customer Segment Outlook

Construction & Infrastructure

Commercial /

Industrial

Energy &

Natural Resources

Government /

Institutions

Engineering & Architecture - 3% Highway & Heavy Construction - 4% Home Builders & Developers - 12%

Non-Residential & GCs - 13%

Subcontractors - 10%

Agriculture, Forestry, Fishing - 1%

Other - 2%

Manufacturing - 9%

Professional Services - 16%

Arts, Media, Hotels, Entertainment - 2%

Retail & Wholesale Trade - 14%

Energy & Natural Resources - 6%

Education - 5%

Government - 2%

Healthcare - 1%

• Continued multi-year demand from strategic onshoring with infrastructure demand beginning in H2 2024, creating tailwinds in manufacturing, industrial, education, and event-driven projects.
• Non-residentialsquare foot starts down 13% Y/Y in Q1 2024 and 4% above 2019 levels.
• Demand across customer segments support unit on rent inflection in H2 2024.

1 Based on Q1 2024.	10