[13] In 2019, Kerr indicated her interest to play in Europe, and having fielded multiple offers from clubs such as Olympique Lyonnais,[14] Kerr ultimately signed with Chelsea, so far winning 8 trophies with the club, including back-to-back-to-back Women's Super League titles, as well as helping the team reach the UEFA Women's Champions League final for the first time in 2021.

[16] In 2021, she captained the team to their historic first ever semi-final of a major tournament during the delayed 2020 Summer Olympics, resulting in their best ever 4th-place finish.

Head coach Aaran Lines said of Kerr, "With her attributes – her speed, athleticism and instincts – if she continues to develop at the rate she is, Sam can become one of the best strikers in the world.

[35] Following the 2014 season, Kerr was traded to Sky Blue FC in exchange for Elizabeth Eddy and a first-round pick—fourth overall—in the 2015 NWSL College Draft.

[45] In the 2016–17 W-League season she scored ten goals, led the team to the Grand Final, and earned the Julie Dolan Medal and the Penny Tanner Media MVP Award.

[49][50] In 2015, Kerr joined Matildas teammate Caitlin Foord at Sky Blue FC following their participation at the FIFA Women's World Cup in Canada.

[13] During the 2016 season, Kerr made nine appearances for Sky Blue after being away with the national team in preparation for the 2016 Rio Olympics.

[53] In the 2017 season, Kerr set a new NWSL record when she scored 4 goals in a single game after being down 3–0 to Seattle Reign at halftime.

[59][60] At the end of the 2019 season, Kerr and the Chicago Red Stars made their first appearance in the NWSL Championship, losing 4–0 to North Carolina Courage.

[63] Kerr also received, for the third year in a row, the NWSL Golden Boot, leading the league with 18 goals and five assists, despite missing some games over the summer to play with Australia in the World Cup.

At the 2020 Women's FA Community Shield on 29 August 2020, Kerr created a series of goal scoring opportunities before being substituted in Chelsea's 2–0 win over Manchester City.

[72] That same season, Kerr helped Chelsea reach the final of the UEFA Women's Champions League for the first time, before being defeated by Barcelona.

[73] During the 2021–22 WSL season, Kerr continued exhibiting fine form and was nominated for the Barclays Player of the Month for September.

On 16 November 2021, Kerr signed a two-year contract extension, keeping her at the club until the end of the 2023–24 season, saying: "I can't see myself going anywhere else in the world or leaving Europe, having what I have at Chelsea.

[75] On 5 December, Kerr scored a brace in the delayed FA Cup final against Arsenal, winning Player of the Match, and helping her team lift the trophy and secure the domestic quadruple of the 2020–21 season, the first English women's club to achieve the feat.

[84] The striker scored a number of important goals during the season, including a crucial 92nd-minute winner against Aston Villa at Kingsmeadow in March 2022 to keep the Blues' title hopes alive.

[100][101] She made her World Cup debut coming on as a substitute in the 79th minute of Australia's first group stage match against Brazil.

[105][106] After injuring her knee in December 2014 and undergoing surgery,[107] Kerr worked hard with fitness coach Aaron Holt to recover ahead of the 2015 FIFA Women's World Cup in Canada.

[119] In February 2019, Kerr was named captain of the Matildas by newly appointed head coach Ante Milicic.

[121] During the team's first group stage match at the 2019 FIFA Women's World Cup in France, she opened up an early lead against Italy after scoring a goal off a penalty kick rebound, though Australia ultimately lost 2–1 in stoppage time.

Kerr's goal was her first at a World Cup tournament and she celebrated by punching the corner flag to honour Tim Cahill, the all-time leading goalscorer for the Socceroos.

[128] Kerr's five goals at the tournament ranked fourth highest behind Ellen White of England and Americans Alex Morgan and Megan Rapinoe, who all scored six.

[141] Kerr made her first appearance in the 2023 World Cup in the 80th minute of the Matildas' win in the round of 16 clash with Denmark.

[145][146][147] Due to her ACL injury in January 2024 the footballer was unable to participate in 2024 AFC Women's Olympic Qualifying Tournament's third round in February.

[151] Kerr was featured on the cover of the July 2011 issue of Australian FourFourTwo along with four of her national team teammates: Melissa Barbieri, Kyah Simon, Thea Slatyer, and Sarah Walsh.

[155] In 2019, she starred in a commercial, Dream Further, that aired during the Champions League Final and 2019 FIFA Women's World Cup and also featured Gerard Piqué, Alex Scott, Neymar Jr., Crystal Dunn, Lieke Martens and Philippe Coutinho.

[156] The same year, her trademark backflip was featured in the Nike ad, Dream Crazier along with other women athletes like Serena Williams, Megan Rapinoe, and Diana Taurasi and aired during the 91st Academy Awards.

[165] In the Australian Football League (AFL), Kerr is a supporter of the West Coast Eagles and was the club's number-one ticket holder in 2019 and 2020.

[169] Kerr was previously in a relationship with former Perth Glory and Chicago Red Stars teammate Nikki Stanton.

[170] In Twickenham on 30 January 2023, Kerr was detained overnight after vomiting out of a taxi window and disputing the driver's clean up fee.