Founded in Indianapolis, Indiana in 1942 by Lewis Levy and Joseph Calderon, the firm began as a small practice. Irwin Katz joined Levy & Calderon in 1952, and his name was added to the firm's that same year. 

After the passings of Joseph Calderon and Lewis Levy, the firm became known as Irwin Katz & Co. It took on the name of Katz, Sapper & Miller in 1975 to reflect the roles of Theodore Sapper, who retired from the firm in 1988 and passed away in 2004, and Curtis Miller, who served as the firm's managing partner for 25 years and now serves as chairman of the board. David Resnick was named managing partner in 2002, a role he holds to this day.

Irwin Katz passed away in 2015 at the age of 96. Katz came to the firm with a belief that there is more to a business than just the accounting ledger, stating "We should make the numbers come to life." His inquisitive nature and motivation to understand his clients' business needs has extended into Katz, Sapper & Miller's culture today.

“To understand what the numbers mean, you have to look beyond the numbers. You have to see the business at work.”

Irwin Katz, Katz, Sapper & Miller