CHICAGO, IL / ACCESS Newswire / June 15, 2026 / Old Second National Bank welcomes the addition of Michael Graf as Senior Managing Director and Head of Middle Market Banking. He has more than 30 years of experience serving middle market clients throughout the greater Chicago area.

Prior to joining Old Second, Michael spent 14 years at First Midwest Bank/Old National Bank, where he held a series of leadership roles within the Corporate Banking division, most recently serving as Group Head of Middle Market Banking. Earlier in his career, he held multiple lending positions within the Metropolitan Bank Group at LaSalle Bank in Chicago, culminating in his role as Senior Vice President and Team Lead.

Michael earned his bachelor's degree from Marquette University and holds an MBA from Loyola University Chicago. He remains actively engaged with Marquette University as a mentor within the College of Business Administration. In addition, he is a longtime member of several professional and civic organizations, including the Association for Corporate Growth and the Turnaround Management Association, and he is involved with the Chicago Southland Economic Development Corporation. Michael also serves on the Chairman's Advisory Council of the Big Shoulders Fund.

About Old Second Bancorp, Inc.: Old Second Bancorp, Inc., headquartered in Aurora, Illinois, is the bank holding company for Old Second National Bank, which celebrated 150 years of operation in 2021. Old Second's common stock trades on The NASDAQ Stock Market under the symbol "OSBC". More information about Old Second is available by visiting the "Investor Relations" section of its website: www.oldsecond.com.

As of March 31, 2026, Old Second has approximately $6.8 billion in assets, $5.6 billion in deposits and $5.2 billion in loans.

Old Second National Bank, Member FDIC.

Contact:

Bradley S. Adams EVP, Chief Operating Officer and Chief Financial Officer (630) 906-5484

SOURCE: Old Second Bancorp Inc.