John O'Connor

Academic Degrees

• BS, Accounting - DePaul University
• MBA - Kellogg School of Management, Northwestern University

Professional Certifications

• Certified Public Accountant (CPA)
• Certified Fraud Examiner (CFE)
• Certified Financial Planner (CFP) — Inactive

Leadership Roles

• Association for Corporate Growth (ACG Chicago) - Board President
• AgeOptions - Finance Committee Chair
• Ledger & Quill - Board Member

Biography

John O’Connor is an audit partner emeritus from Plante Moran’s Chicago office, where he specialized in complex accounting and auditing matters for public, private equity–owned, and family businesses, working closely with both clients and staff.

A graduate of DePaul University, John spent 40 years in public accounting, beginning his career with Deloitte in Chicago and later serving 23 years as a partner at Plante Moran. He advised clients across the full business lifecycle, from transaction accounting through exit, with deep experience in sell-side preparation and accounting matters related to deal execution.

In the latter part of his career, John focused extensively on private equity–backed companies, supporting confidential information memorandum (CIM) development, quality of earnings, forecasting, buyer diligence, and close and post-close transition activities. Over his career, John worked closely with staff development and was an early leader and champion of Plante Moran’s diversity initiatives.

John has remained deeply engaged with DePaul University’s Driehaus College of Business. He led Plante Moran’s partnership with DePaul, mentored students in ACC 250, and regularly participated in panel discussions, classroom visits, and student organization events. He is passionate about helping students and early-career professionals build successful accounting careers.

He is also active in several professional organizations and boards, including Ledger & Quill, the donor society of the School of Accountancy & MIS.