SUN COMMUNITIES INC

Evaluation of Disclosure Controls and Procedures

We maintain disclosure controls and procedures designed to ensure that information required to be disclosed in reports filed under the Exchange Act is recorded, processed, summarized and reported within the specified time periods and accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate to allow timely decisions regarding required disclosure. 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 was made under the supervision and with the participation of our management, including our principal executive officer and principal financial officer.

Based upon this evaluation, our principal executive officer and principal financial officer have concluded that, as of December 31, 2024, our disclosure controls and procedures were not effective as of that date due to a material weakness in internal control over financial reporting relating to our risk assessment process, as described below.

Management's Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining effective internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act. This system is designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of consolidated financial statements for external purposes in accordance with GAAP. Because of the inherent limitations of internal control over financial reporting, including the possibility of collusion or improper management override of controls, misstatements due to error or fraud may not be prevented or detected on a timely basis.

Our management performed an assessment of the effectiveness of our internal control over financial reporting as of December 31, 2024, utilizing the criteria discussed in the Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. The objective of this assessment was to determine whether our internal control over financial reporting was effective as of December 31, 2024. Based on management's assessment, we have concluded that our internal control over financial reporting was ineffective as of December 31, 2024, due to the material weakness relating to our risk assessment process described below.

A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of our annual or interim financial statements will not be prevented or detected on a timely basis.

Material Weakness - Risk Assessment and Response

As of December 31, 2024, we had a material weakness because we did not have an effective risk assessment and response process ("risk assessment") that defined clear financial reporting objectives, that identified and evaluated risks of misstatement due to errors over certain financial reporting processes, or that developed internal controls to mitigate those risks. As part of management's evaluation of this material weakness, it has been identified that certain other deficiencies in control activities have materialized as a result of the deficiency in the Company's risk assessment. Specifically, as of December 31, 2024, there are deficiencies in the design and implementation of the Company's internal controls due to ineffective risk assessment resulting in the following:

•Inadequate identification and timely consideration of accounting for certain transactions.

•Existence of inappropriate access and insufficient segregation of duties ("SOD") upon implementation of a new integrated enterprise resource planning and general ledger ("ERP") system during 2024.

•Reliance on information and reports from our new ERP used in internal controls over financial reporting without adequately validating their completeness and accuracy.

•Inadequate assessment of the impact our new ERP had on certain processes and related control activities, including investment property, inventory of manufactured homes, and the review and approval of manual journal entries.

These deficiencies relate to both information technology general controls, manual controls, and manual controls dependent upon information technology that could impact the consistency, timeliness and accuracy of financial reporting in accordance with GAAP. These matters did not result in material misstatements to the Consolidated Financial Statements in the current period, but do allow for the reasonable possibility that material misstatements would not be prevented or detected on a timely basis.

Plan for Remediation of the Material Weakness

We have invested considerable time and resources to undertake a number of actions related to the material weakness relating to our risk assessment process and we are in the process of developing and implementing additional actions as part of a detailed plan for remediation. The Audit Committee has continued to actively oversee these remediation plans, monitoring plan progression and ensuring appropriate resources are allocated and implemented to effectively execute management's plan. The actions that we have undertaken are as follows:

•Implemented more frequent communication between those charged with governance and management regarding progression on material weakness remediation. Additionally, an internal control project plan was developed and has begun to be implemented under the monitoring and supervision of the Audit Committee.

•Engaged a third-party accounting and advisory firm to assist us with completing a comprehensive risk assessment and a gap analysis of certain aspects of our risk control matrix, including identification of risks of material misstatement, to assess the potential need for any new controls or controls that need to be redesigned to adequately address the corresponding financial reporting risk.

•Completed a risk-based review of user access to our ERP and when necessary modified roles or user access to eliminate SOD conflicts. We engaged a third-party accounting and advisory firm to confirm the scope and execution of this access review.

•Implemented a third-party software solution to assist management with monitoring user access to our ERP system to identify and prevent user access that violates our established SOD ruleset.

•Identified a complete population of information and reports used in internal controls over financial reporting and began validating the completeness and accuracy of this information and reports generated from our new ERP.

Additionally, management's detailed plan for remediation includes the following:

•Redesigning the review control related to certain manual journal entries.

•Ensuring internal control processes include policies and procedures to ensure that all information used in the performance of internal controls is validated for completeness and accuracy.

•Redesigning or developing new internal controls to address risks, if any, determined to not be adequately mitigated following the completion of the risk assessment and gap analysis currently in process.

•Refining and developing additional SOD rules as needed based on the results of the review of our SOD ruleset by the third-party accounting and advisory firm.

While we believe our remediation efforts above will improve the effectiveness of our internal control over financial reporting, we cannot assure that the measures will be sufficient to remediate the material weakness we have identified or will prevent potential future material weaknesses. In addition, many of the improvements have not operated for a sufficient period of time to be able to conclude on the effectiveness of relevant internal controls. Accordingly, we will continue to monitor, with oversight from our Board of Directors, and evaluate the effectiveness of our internal control over financial reporting and further enhance our plan for remediation as necessary.

Remediation of Previously Disclosed Material Weaknesses

We previously identified and disclosed in Part II, Item 9A, "Controls and Procedures" of our Annual Report on Form 10-K for the year ended December 31, 2023, a material weakness related to the design of management's review controls of potential triggering events related to the evaluation for impairment of goodwill relating to our Park Holidays reporting unit within the UK reporting segment. During 2024 the goodwill at the UK reporting segment was fully impaired. The Company has concluded that there is no longer a risk of material misstatement related to this management review control.

We also previously identified and disclosed in Part I, Item 4, "Controls and Procedures" of our Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2024, a material weakness related to the design of management's review controls for evaluating long-lived assets for impairment, relating to certain long-lived asset groupings and properties within the UK reporting segment. As of December 31, 2024, we determined that this previously reported material weakness is a result of the risk assessment material weakness described above and will be covered by the remediation activities described above.

Attestation Report of Registered Public Accounting Firm

The effectiveness of our internal control over financial reporting has been audited by Grant Thornton LLP, an independent registered public accounting firm, as stated in its report included herein. This report contains an adverse opinion on the effectiveness of our internal control over financial reporting.

Changes in Internal Control over Financial Reporting

Except as discussed above, there were no changes in internal control over financial reporting during the quarter ended December 31, 2024, that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.