• 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

  • KOS Book Club: The Productivity Project - By: Bruce Kreisman, Kathy Stanley, Olga Bernick, Cameron Kinley and Abigail Schaffer - At KOS we recognize that a successful professional utilizes various skills while servicing our clients. The most obvious are technical skills, whether in accounting, auditing, tax or consulting. But a well-rounded professional will also be strong in the so-called "soft skills," things they do not necessarily... More →
  • Should You Join in Crowdfunding? - Modern means for start-ups - Do you need an influx of cash to launch a business venture devoted to your personal passion? You can do things the old-fashioned way and issue an initial public offering (IPO) for review by prospective investors. Although IPOs remain viable for some types of businesses, especially larger ones, they can cost time and money, not to mention the hassles. Alternatively,... More →
  • KOS is Hiring! - Help spread the word! We are actively seeking exceptional candidates for the following positions: - Accounting and Auditing Supervisors and Managers (4-6 years of previous public accounting experience required) - The KOS Difference - Direct Client/ Partner Contact*Great People*Challenging Work*Flex-Time*Work Variety - Tell your friends, networks and college age students to spread the word and... More →
  • News Briefs - Tax Return Reminders - The due date for filing partnership tax returns has moved to March 15, while the deadline for C corporations has changed to April 15. (Deadlines are pushed out to the next business day for holidays and weekends.) The changes take effect for 2016 returns. - Resigning Times - Can you require an employee who is resigning to stay with your company? It depends. If there is a... More →
  • Adding a Prenup to Your Estate Plan - Key component for wealth protection - Are nuptials on the way? Suppose that you are going to be married soon. Perhaps it’s a second or even third marriage. Or maybe another family member—for example, a son or daughter, or a grandchild—will be the one walking down the aisle. In any event, it should be a blissful occasion. - But you cannot ignore reality. With so many marriages in this... More →
"[KOS is] friendly, approachable, and always willing to help me find the answer to a question." - Joan Meyer La James International College