ONB Investment Thesis 4Q24

Exhibit 99.1

4th Quarter 2024

Investment Thesis

February 10, 2025

Forward-Looking Statements

These materials contain certain "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 (the "Act"), notwithstanding that such statements are not specifically identified as such. In addition, certain statements may be contained in our future filings with the Securities and Exchange Commission ("SEC"), in press releases, and in oral and written statements made by Old National Bancorp ("Old National", "ONB" or the "Company") that are not statements of historical fact and constitute forward-looking statements within the meaning of the Act. These statements include, but are not limited to, descriptions of Old National's financial condition, results of operations, asset and credit quality trends, profitability and business plans or opportunities. Forward-looking statements can be identified by the use of words such as "anticipate," "believe," "contemplate," "continue," "could," "estimate," "expect," "guidance," "intend," "may," "outlook," "plan," "potential," "predict," "should," "would," and "will," and other words of similar meaning. These forward-looking statements express management's current expectations or forecasts of future events and, by their nature, are subject to risks and uncertainties. There are a number of factors that could cause actual results or outcomes to differ materially from those in such statements, including, but not limited to: competition; government legislation, regulations and policies; the ability of Old National to execute its business plan; unanticipated changes in our liquidity position, including but not limited to changes in our access to sources of liquidity and capital to address our liquidity needs; changes in economic conditions and economic and business uncertainty which could materially impact credit quality trends and the ability to generate loans and gather deposits; inflation and governmental responses to inflation, including increasing interest rates; market, economic, operational, liquidity, credit, and interest rate risks associated with our business; our ability to successfully manage our credit risk and the sufficiency of our allowance for credit losses; the failure to obtain necessary regulatory approvals for the merger (the "Merger") between Old National and Bremer (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the proposed transaction) and the possibility that the Merger does not close when expected or at all because required regulatory approvals, the approval by Bremer's shareholders, or other approvals and the other conditions to closing are not received or satisfied on a timely basis or at all; the occurrence of any event, change or other circumstances that could give rise to the right of one or both of the parties to terminate the merger agreement between Old National and Bremer; the expected cost savings, synergies and other financial benefits from the Merger not being realized within the expected time frames and costs or difficulties relating to integration matters being greater than expected; potential adverse reactions or changes to business or employee relationships, including those resulting from the completion of the Merger; the impact of purchase accounting with respect to the Merger, or any change in the assumptions used regarding the assets acquired and liabilities assumed to determine their fair value and credit marks; risks relating to the potential dilutive effect of shares of Old National's common stock to be issued in the Merger; the potential impact of future business combinations on our performance and financial condition, including our ability to successfully integrate the businesses, the success of revenue-generating and cost reduction initiatives and the diversion of management's attention from ongoing business operations and opportunities; failure or circumvention of our internal controls; operational risks or risk management failures by us or critical third parties, including without limitation with respect to data processing, information systems, cybersecurity, technological changes, vendor issues, business interruption, and fraud risks; significant changes in accounting, tax or regulatory practices or requirements; new legal obligations or liabilities; disruptive technologies in payment systems and other services traditionally provided by banks; failure or disruption of our information systems; computer hacking and other cybersecurity threats; the effects of climate change on Old National and its customers, borrowers, or service providers; political and economic uncertainty and instability; the impacts of pandemics, epidemics and other infectious disease outbreaks; other matters discussed in these materials; and other factors identified in our Annual Report on Form 10-K for the year ended December 31, 2023 and other filings with the SEC. These forward-looking statements are made only as of the date of these materials and are not guarantees of future results, performance or outcomes, and Old National does not undertake an obligation to update these forward-looking statements to reflect events or conditions after the date of these materials.

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Non-GAAP Financial Measures

The Company's accounting and reporting policies conform to U.S. generally accepted accounting principles ("GAAP") and general practices within the banking industry. As a supplement to GAAP, the Company provides non-GAAP performance results, which the Company believes are useful because they assist investors in assessing the Company's operating performance. Where non-GAAP financial measures are used, the comparable GAAP financial measure, as well as the reconciliation to the comparable GAAP financial measure, can be found in the "Appendix to Non-GAAP Reconciliation" of this financial review.

The Company presents earnings per share ("EPS"), the efficiency ratio, retuon average common equity, retuon average tangible common equity, and net income applicable to common shares, all adjusted for certain notable items. These items include merger-related charges associated with completed and pending acquisitions, separation expense, current expected credit loss ("CECL") Day 1 non-purchase credit deteriorated provision expense, debt securities gains/losses, distribution of excess pension assets expense, Federal Deposit Insurance Corporation ("FDIC") special assessment expense, gain on sale of Visa Class B restricted shares, contract termination charges, expenses related to the tragic April 10, 2023 event at our downtown Louisville location ("Louisville expenses"), and property optimization charges. Management believes excluding these items from EPS, the efficiency ratio, retuon average common equity, and retuon average tangible common equity may be useful in assessing the Company's underlying operational performance since these items do not pertain to its core business operations and their exclusion may facilitate better comparability between periods. Management believes that excluding merger-related charges from these metrics may be useful to the Company, as well as analysts and investors, since these expenses can vary significantly based on the size, type, and structure of each acquisition. Additionally, management believes excluding these items from these metrics may enhance comparability for peer comparison purposes.

The Company presents adjusted noninterest expense, which excludes merger-related charges, separation expense, distribution of excess pension assets expense, FDIC special assessment expense, contract termination charges, Louisville expenses, property optimization charges, as well as adjusted noninterest income, which excludes debt securities gains/losses and the gain on sale of Visa Class B restricted shares. Management believes that excluding these items from noninterest expense and noninterest income may be useful in assessing the Company's underlying operational performance as these items either do not pertain to its core business operations or their exclusion may facilitate better comparability between periods and for peer comparison purposes.

The tax-equivalent adjustment to net interest income and net interest margin recognizes the income tax savings when comparing taxable and tax-exempt assets. Interest income and yields on tax-exempt securities and loans are presented using the current federal income tax rate of 21%. Management believes that it is standard practice in the banking industry to present net interest income and net interest margin on a fully tax-equivalent basis and that it may enhance comparability for peer comparison purposes.

In management's view, tangible common equity measures are capital adequacy metrics that may be meaningful to the Company, as well as analysts and investors, in assessing the Company's use of equity and in facilitating comparisons with peers. These non-GAAP measures are valuable indicators of a financial institution's capital strength since they eliminate intangible assets from stockholders' equity and retain the effect of accumulated other comprehensive loss in stockholders' equity.

Although intended to enhance investors' understanding of the Company's business and performance, these non-GAAP financial measures should not be considered an alternative to GAAP. In addition, these non-GAAP financial measures may differ from those used by other financial institutions to assess their business and performance. See the following reconciliations in the "Non-GAAP Reconciliations" section in the appendix for details on the calculation of these measures to the extent presented herein.

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