Andrews then joined the U.S. General Accounting Office and became the first director of its Corporation Audits Division, then returned to private practice in Richmond in 1947.

Andrews ran for president as the States' Rights Party candidate in the election of 1956; his running mate was former Congressman Thomas H. Werdel.

While running for office, Andrews was a trustee and visiting lecturer of the University of Virginia's Graduate School of Business Administration (1955–56).

In 1965, Andrews retired from his accounting businesses and worked with his sons in organizing a variety of service enterprise firms.

His son Thomas Coleman Andrews Jr. would become a prominent political organizer and segregationist who thrice won election to the Virginia House of Delegates in the 1960s and supported Alabama Governor George C. Wallace for president in 1968.