• Welcome to KOS!

    With an over 80-year history, the mid-sized accounting firm of Kessler Orlean Silver & Co., P.C., provides innovative accounting solutions to business owners, executives and managers, private investors, and professionals.

    Our down-to-earth style and practical experience come from a long-time culture of helping people and feeling passionate about doing so!

  • What Sets Us Apart

    We care. Pure and simple.

    ‘Above and beyond’ dedication to client service is our highest priority. Clients tell us they appreciate our accessibility and outstanding service. We believe it’s essential that you receive our close personal attention with prompt answers and new ideas.

    No situation is too tough or too routine. Every challenge is viewed with a fresh eye and resolved with a creative solution.

    By placing our service standards front and center in the way we conduct business, you can expect to receive the highest quality service while we help you improve your business or personal financials.

  • On the surface, accounting firms seem a lot alike. But some stand out from the crowd. So what makes KOS different? Our people. Sincerely caring, really listening, and then putting your outcome ahead of our interests. It’s our exuberant: to put you above all else.


    Based in Deerfield, a Chicago suburb, KOS serves businesses and individuals in multiple states providing business consulting, accounting and bookkeeping, and tax services.

Firm Profile

Learn more about the firm’s people, philosophies, and client service commitment.


Our monthly newsletter is available online and keeps you current on tax and financial matters.

KOS News Ticker

  • Check out KOS Partner Geoff Harlow in IL CPA Society Video - Congrats to KOS Partner Geoff Harlow on a job well done speaking on behalf of why CPA firms and businesses should consider diversity & inclusion as part of their plan for success. - Geoff is quoted in the Illinois CPA Society's new CEO video encouraging executives to think differently about the future of the CPA profession. - Click on the link to watch the video and hear some compelling... More →
  • KOS to Participate in the Illinois CPA Day of Service - Governor Rauner has officially proclaimed September 23, 2016 to be CPA Day of Service throughout Illinois. - KOS is proud to be part of this wonderful day. Employees from the firm will be traveling to the Feed My Starving Children (FMSC) facility in Libertyville, IL for an afternoon of helping others. - KOS chose to work with FMSC because of their emphasis on small group involvement and... More →
  • Have You Designated Your Beneficiaries? - A key component of estate planning - Most of us lead hectic lives, but as part of an estate plan, it is important to take time to designate or update beneficiaries for all your assets. Notably, you should be aware that designations for retirement plans and life insurance policies supersede beneficiary dispositions in your will. Keeping that in mind, here are several practical suggestions. -... More →
  • Crash Course on Education Tax Breaks - Choose one of three tax-savers - Now that your children are back in school, you might consider the available tax breaks for higher education expenses. Following extensions and modifications under the Protecting Americans from Tax Hikes (PATH) Act of 2015, there are three primary tax provisions that may benefit parents: the American Opportunity Tax Credit (AOTC), the Lifetime Learning Credit (LLC)... More →
  • KOS is Hiring! - We are actively seeking exceptional candidates for the following positions: - Tax Interns to work this busy season February to April 15, 2017 - Staff Accountants (December 2016 and May 2017 Graduates) - Accounting and Auditing Supervisors - KOS will be on-campus during the month of September for interviews and attending career fairs at the following schools: University of Illinois at Chicago... More →
"[KOS is] friendly, approachable, and always willing to help me find the answer to a question." - Joan Meyer La James International College