Mars is a heiress to Mars, Inc. shares. As a member of the Mars family, Mars' shares of Mars, Incorporated and other assets were estimated by Forbes magazine in January 2019 to be worth $23.5 billion, making her the 18th richest American, and #34 on its list of "The World's Billionaires". Mars was active in Mars, Inc. from 1982, when she joined the company as Food Product Group President, until her retirement in 2001. Reported by Forbes June 2019, Mars is the wealthiest resident living in Virginia with an estimate 28.1 billion dollar net worth.