While head of United States Steel, Farrell increased the steel output of the company from 6 million tons to 29 million tons. Upon his retirement, United States Steel owned over 1 million acres of coal and coke properties, 25 railroad lines with nearly 3,000 miles of track, and 700 sailing vessels. In 1931, Farrell oversaw gross sales of $730 million and over 53,000 full-time and 150,000 part-time employees.