The firm traces its beginnings to 1935 with the founding of the firm McMartin, Herrick & Langdon. In 1954, the firm hired David Belin, a recent Army veteran from Sioux City with degrees from the University of Michigan's College of Literature, Science and the Arts, Business School, and Law School. Belin soon built one of the preeminent corporate law practices in the state. The firm changed its name to Herrick, Langdon, Sandblom & Belin in 1962.

Belin's reputation as a brilliant legal mind traveled well beyond Iowa's borders. After the assassination of President John F. Kennedy, Belin was made counsel to the Warren Commission, charged with investigating the president's assassination. Belin remained a vociferous defender of the findings of the Warren Report until his death. (As renowned journalist Andrew Sullivan wrote in The New York Times shortly after Belin's passing, "As he lay in a coma, friends confirmed his lack of consciousness by whispering into his ear that they believed there had been a government conspiracy to kill President Kennedy. For the first time, Belin said nothing in response.") In 1975, President Gerald Ford appointed Belin executive director of the Rockefeller Commission, charged with investigating the secret activities of the Central Intelligence Agency and other intelligence agencies within the United States.

In 1978, the firm took the name Belin, Harris, Helmick & Tesdell, and the firm's evolution and expansion began in earnest. In 1986, former Iowa Supreme Court Justice Mark McCormick joined the firm, cementing the firm's strong litigation practice to match its robust corporate practice. The firm later became Belin Lamson McCormick Zumbach Flynn in 1997. In 2009, the firm shortened and simplified its name, for the last time, to Belin McCormick, P.C. Although David Belin passed away in 1999, Mark McCormick continues his remarkable practice with the firm.

Current or former Belin McCormick attorneys have held civic leadership positions at the highest levels, including chairing the United States Olympic Committee, the Greater Des Moines Partnership, and the United Way of Central Iowa Campaign. Former attorneys at the firm have served as United States Attorney and Iowa Attorney General. The firm boasts a particularly impressive history of attorneys who have gone on to prestigious positions in the judiciary. Belin McCormick currently counts among its former partners members of the Iowa Court of Appeals, the Iowa Supreme Court, and the United States Court of Appeals for the Eighth Circuit.