Peratrovich worked as an accountant in Oregon for several years. He returned to Klawock, Alaska and opened the Klawock Cash Store. Peratrovich served as mayor of Klawock as a Democrat.
In 1945–46, Peratrovich served in the Alaska Territorial House of Representatives. He then served in the Alaska Territorial Senate from 1947 to 1951 and from 1957 to 1959. Peratrovich served in the first Alaska Constitutional Convention of 1955. From 1959 to 1967, he served in the Alaska Senate. Peratrovich served in the Alaska House of Representatives from 1969 to 1973.
Peratrovich's brother, Roy Peratrovich, married Elizabeth Peratrovich, a Native leader who led the petition for the Anti-discrimination Act of 1945 in Alaska.[3] He died at the Ketchikan Pioneer Home in Ketchikan, Alaska at the age of 88.[4][5]