[4] Basing herself in The Bronx, New York, alongside her fellow marathon runner and husband Worku Beyi, she began to compete in road races in the United States in 2009.

She was tenth at the Peachtree Road Race on July 4, but returned to her winning ways at the Buffalo 4-Miler and Chris Thater Memorial 5K.

[11] At the beginning of 2011, Deba defeated pre-race favourite Mare Dibaba to win the Los Angeles Marathon.

[19] In 2014, Deba ran the New York Half in 1:08:59, and won the 2014 Boston Marathon in 2:19:59,[1] a title awarded in December 2016 after Rita Jeptoo was disqualified over doping.

[2][20] In April 2024, The Wall Street Journal reported she was still awaiting payment of the winner's prize money for her first place finish in that event, as well as the bonus for setting the women's course record.

[21] In May 2024, businessman Doug Guyer paid the missing prize money after reading the Journal article and urged Marathon organizers to pay the remaining bonus.