is an American former professional soccer player. From 2014 to 2021, she played for National Women's Soccer League club Chicago Red Stars, and in 2023 she played for Angel City FC. A member of the United States women's national team from 2013 to 2023, she first appeared for the United States national team during an international friendly against Scotland on February 9, 2013, eventually making 123 total appearances for the team.

Ertz played collegiate soccer with the Santa Clara University Broncos from 2010 to 2013. Following her collegiate career, Ertz was selected third overall by the Chicago Red Stars in the 2014 NWSL College Draft and was named NWSL Rookie of the Year. Ertz helped the United States win their titles at the 2015 and 2019 FIFA Women's World Cup. At 23, she was the second youngest member of the 2015 team behind 22-year-old Morgan Brian. Ertz played every minute of all seven games of the 2015 tournament and was subsequently named to the FIFA Women's World Cup All-Star Team. After the 2023 World Cup, Ertz retired from international soccer.

After moving to center midfield for club and country in 2017, Ertz was awarded U.S. Soccer Female Player of the Year.

Ertz was again nominated for U.S. Soccer Female Player of the Year in 2018 and won the U.S. Soccer Female Player of the Year in 2019. Her husband Zach plays in the National Football League (NFL).