Custom Truck One Source Inc

(a)Evaluation of Disclosure Controls and Procedures

In accordance with Securities Exchange Act Rules 13a-15(e) and 15d-15(e), our management, under the supervision of our Chief Executive Officer and Chief Financial Officer, conducted an evaluation of the effectiveness of the design and operation of our disclosure controls and procedures as of the end of the period covered by this Annual Report on Form 10-K. Based on that evaluation, the Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were not effective as of December 31, 2023 because of the material weakness in our internal control over financial reporting described below.

(b)Management’s Report on Internal Control over Financial Reporting

Management is responsible for establishing and maintaining adequate internal control over financial reporting for the Company. Internal control over financial reporting is defined in Rules 13a-15(f) and 15d-15(f) promulgated under the Securities Exchange Act of 1934, as amended, as a process designed by, or under the supervision of, the Company’s principal executive and principal financial officers and effected by the Company’s board of directors, management and other personnel, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles and includes those policies and procedures that:

Pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of the assets of the Company;

Provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the Company are being made only in accordance with authorizations of management and directors of the Company; and

Provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the Company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Internal control over financial reporting cannot provide absolute assurance of achieving financial reporting objectives because of its inherent limitations. Internal control over financial reporting is a process that involves human diligence and compliance and is subject to lapses in judgment and breakdowns resulting from human failures. Internal control over financial reporting can also be circumvented by collusion or improper management override. Because of such limitations, there is a risk that material misstatements may not be prevented or detected on a timely basis by internal control over financial reporting. However, these inherent limitations are known features of the financial reporting process. Therefore, it is possible to design into the process safeguards to reduce, though not eliminate, this risk.

The Company’s management assessed the effectiveness of the Company’s internal control over financial reporting as of December 31, 2023. In making this assessment, the Company’s management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (“2013 framework”) (“COSO”) in Internal Control-Integrated Framework.

Based on that assessment, the Chief Executive Officer and Chief Financial Officer concluded as of December 31, 2023, the Company’s internal control over financial reporting was not effective, due to the material weakness described below.

Inadequate General Information Technology Controls and Business Process Controls

On April 1, 2021, we completed the acquisition of Custom Truck LP, which resulted in a significant change in the Company’s internal control over financial reporting. We are in the process of integrating policies, processes, people, technology and operations for the combined company. As part of this integration, we have identified deficiencies in the design and operating effectiveness of internal controls associated with the control activities component of the COSO framework. These include:

During the fourth quarter ended December 31, 2021, we identified control deficiencies related to overall ITGCs for both user access and program change-management for systems supporting all of the Company’s internal control processes and controls, controls over the completeness and accuracy of information used in business process controls and management review controls. Our business process controls (automated and manual) and management review controls were also deemed ineffective because they are adversely impacted by ineffective ITGCs. These control deficiencies could result in misstatements potentially impacting all financial statement accounts and disclosures that may not be prevented or detected.

Accordingly, these deficiencies constituted a pervasive material weakness. The pervasive material weakness did not result in any identified misstatements to our consolidated financial statements, and there were no changes to previously released financial results.

(c)Status of Remediation of the Pervasive Material Weakness in Internal Control Over Financial Reporting

We have devoted and continue to devote substantial resources and effort to remediating the pervasive material weakness identified in fiscal year 2021. While we continue to enhance our overall internal control over financial reporting environment to ensure that it is comprehensive, management concluded that a portion of the pervasive material weakness that related to ITGCs identified in fiscal year 2021 and reported in our Annual Report on Form 10-K as of March 14, 2023, was remediated in fiscal year 2023. We implemented changes associated with the design, implementation, and monitoring ITGCs in the areas of user access and program change-management for systems supporting all of the Company’s primary internal control processes to ensure that ITGCs are designed and operating effectively. We also established controls to ensure appropriate authorization of new user access requests, including performance of routine reviews of user access, and controls over program-change management.

Additionally, management is in the process of designing, implementing and monitoring business process level controls that are relevant to all financial statement accounts and disclosures. This pervasive material weakness cannot be considered remediated until the applicable controls are designed and operating effectively for a sufficient period of time, as supported by management’s testing results. The Company’s independent registered public accounting firm that audited the consolidated financial statements included in this Annual Report issued an adverse report on effectiveness of the Company’s internal control over financial reporting as of December 31, 2023.

(d)Changes to Internal Control over Financial Reporting

Other than the ongoing remediation efforts described above, there were no changes to our internal control over financial reporting that occurred during the quarter ended December 31, 2023 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Management’s Certifications

The certifications of the Company’s Chief Executive Officer and Chief Financial Officer required by the Sarbanes-Oxley Act are included as Exhibits 31 and 32 to this Annual Report on Form 10-K.

To the Stockholders and the Board of Directors of Custom Truck One Source, Inc.

Opinion on Internal Control Over Financial Reporting

We have audited Custom Truck One Source, Inc.’s internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria). In our opinion, because of the effect of the material weakness described below on the achievement of the objectives of the control criteria, Custom Truck One Source, Inc. (the Company) has not maintained effective internal control over financial reporting as of December 31, 2023, based on the COSO criteria.

A material weakness is a deficiency, or combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of the company’s annual or interim financial statements will not be prevented or detected on a timely basis. The following material weakness has been identified and included in management’s assessment. Management has identified a material weakness in the design and operation of controls related to:

Not fully designing, implementing and monitoring business process controls (automated and manual) over all accounts and disclosures. Until the applicable controls are designed and operating for a sufficient period of time and management has concluded this, through testing, these control deficiencies could result in misstatements potentially impacting all financial statement accounts and disclosures that may not be prevented or detected.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2023 and 2022, the related consolidated statements of operations and comprehensive income (loss), stockholders’ equity (deficit) and cash flows for each of the three years in the period ended December 31, 2023, and the related notes and financial statement schedule listed in the Index at Item 15(a). This material weakness was considered in determining the nature, timing and extent of audit tests applied in our audit of the 2023 consolidated financial statements, and this report does not affect our report dated March 7, 2024, which expressed an unqualified opinion thereon.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects.

Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Ernst & Young LLP

Kansas City, Missouri

March 7, 2024