Greg Koelling, CPA

Greg Koelling, CPA

P 312.670.7444 | F 312.670.8301

Greg Koelling has been with ORBA since 2001, working in both the audit and tax departments. Over the course of his career, Greg has gained extensive experience serving individuals, partnerships and privately-held corporations. His specialties include federal and state tax planning and consulting for owners and key executives. In addition, he represents taxpayers in front of the Internal Revenue Service and state taxing authorities.

Greg specializes in state tax planning and compliance strategies for multi-state businesses. He also helps clients in the health care field with tax planning, compensation methods and strategic assistance with mergers and acquisitions. Greg also works closely with many real estate development, contracting, manufacturing and distribution, advertising/PR and professional service businesses.

view all

Firms News


ORBA Human Resources Director Sarah Wonnell Appointed Board Chair of Windy City Performing Arts
Ostrow Reisin Berk & Abrams, Ltd. (ORBA), one of Chicago’s largest public accounting firms, is proud to announce that Human Resources Director Sarah Wonnell has been appointed as the new board chair of Windy City Performing Arts (WCPA) for a one-year term. Windy City Performing Arts is a not-for-profit organization that sings to inspire change, celebrate diversity and honor the dignity of the LGBTQ+ community.

view all

Media Mentions




ORBA will gladly provide you with hard copies of the useful guides listed below. Select which guides you would like to receive and submit the form below.

  • Tax Pocket Guide
  • Tax Planning Guide
  • Records Retention Schedule
  • Auto, Travel & Business Log

request guide

Forward Thinking
Forward Thinking