Starting her career in FC Malters before moving to SC Luwin, she then rejected offers from both Germany and USA to sign for Swedish club Umeå IK in Damallsvenskan at the age of 16 in 2007. Following Marta's departure from the club in 2009, Bachmann became a key player at Umeå. She was voted Swiss female Player of the Year in 2009. In 2010, Bachmann joined new Women's Professional Soccer expansion team Atlanta Beat as their No. 1 pick in the 2009 WPS International Draft. After an injury-hit season in the professional WPS, and after her contract with the Atlanta Beat was not renewed, Bachmann rejected offers from Germany, England and the United States to return to Umeå for the 2011 season. She was named the best player of the 2011 season, and subsequently moved to defending champion LdB Malmö. Playing alongside Marta, Mittag and others, she slowly turned into one of the best footballers in the world. She won the Damallsvenskan in her last season with LdB Malmö. On 26 August 2015 it was announced that Bachmann had joined German side VfL Wolfsburg for a contract that will last until 2018. She was chosen Swiss Player of the Year for a second time in 2015. In December 2016, London-based FA WSL club Chelsea announced that Bachmann had agreed to join them when the transfer window opened the following month. In 2018, on 5 May, Bachmann scored twice, including the winning goal, in the Women's FA Cup final against Arsenal, a game which ended 3–1 to Bachmann's team, Chelsea. She was named the Player of the Match by commentator Sue Smith. On 3 July 2020, French club Paris Saint-Germain announced the signing of Bachmann on a two-year deal.
International career
Bachmann played for Switzerland in the 2006 and 2010 editions of the FIFA U-20 Women's World Cup. During the latter tournament she was hampered by a back injury. At the 2009 UEFA Women's Under-19 Championship in Belarus, Bachmann won the UEFA.com Golden Player award. Bachmann made her debut for the Swiss senior team against Sweden in June 2007, while only being 16 years of age. In September 2010 Bachmann scored in Switzerland's 2011 FIFA Women's World Cup qualifying defeat against England, but was criticised for her play acting that led to the dismissal of England goalkeeper Rachel Brown. Bachmann admitted there was no foul and apologised for her actions, while Brown's red card was rescinded on appeal. Bachmann was ruled out of the following play-offs against Denmark due to her persistent back pain. Bachmann's biggest achievement so far was the qualification for the 2015 FIFA Women's World Cup, in Canada. Switzerland had never before qualified for a World Cup. After winning their home game against Malta, the team was sitting in front of the TV watching the game between Denmark and Iceland. If it ended in a draw, the Swiss would secure the group's victory. As said by herself: "When it ended in a draw and it was certain we had won the group, we started dancing on the tables." During the World cup, Switzerland reached the round of 16, with Bachmann scoring three times, all in a 10–1 victory over hapless Ecuador. The Swiss were edged out by hosts Canada, due to one goal by Josée Bélanger, just after the half-time break. After the World Cup, there were multiple clubs interested in the 24-year-old Bachmann, and she chose VfL Wolfsburg.