Finished runner-up at the Evian Masters; tied for second at the CN Canadian Women's Open; fifth at the Avnet LPGA Classic; tied for fifth at the Sime Darby LPGA Malaysia; tied for sixth at the Wegmans LPGA Championship, Navistar LPGA Classic and Mizuno Classic; tied for eighth at the Safeway Classic Presented by Coca-Cola and the Walmart NW Arkansas Championship; tied for ninth at the HSBC Women's Champions. Lewis competed in her first U.S. Solheim Cup Team with a 1-3-0 record.
In 2010, Lewis was denied her first official LPGA victory by Ai Miyazato. She finished the Tres Marias Championship as runner-up having been narrowly defeated by one stroke. She impressed again at the Mizuno Classic where she was able to finish third. She managed to finish in the top 10 on two other occasions in the season.
In 2009, Stacy Lewis’s best finish was a tie for fourth at the Wegmans LPGA, where she carded a season-low 67 during the second round; also carded 67s in the final round of the LPGA Corning Classic, and in the second round of both the Evian Masters and P&G Beauty NW Arkansas Championship Presented by John Q. Hammons; tied for ninth at the McDonald's LPGA Championship Presented by Coca-Cola.
Lewis turned professional in June 2008; she competed in seven events on Tour with two top-10 finishes, including a tie for third at the U.S. Women’s Open and a tie for sixth at the Kapalua LPGA Classic; also competed in two events on the Duramed FUTURES Tour with two top-three finishes; earned medalist honors at the LPGA Final Qualifying Tournament to earn Priority List Category 11 for the 2009 LPGA season.
In 2007, as an amateur, the American carded a career-low 65 to take the first-round lead at the LPGA NW Arkansas Championship Presented by John Q. Hammons before the tournament was rain-shortened and cancelled following 18 holes of play; Lewis also tied for fifth at the Kraft Nabisco Championship to earn low-amateur honors.
As a member of the University of Arkansas women’s golf team, Lewis won 12 collegiate events and was a four-time All-American. She was the 2005 South-eastern Conference (SEC) Freshman of the Year, the 2007 NCAA Division I National Champion and the 2008 SEC Championship Individual Medallist and Player of the Year.