In 2020, at the age of 15, Thompson verbally committed to joining the
Cardinal of
Stanford University starting in the 2023 season. However, she later decommitted to enter the
2023 NWSL Draft.
Angel City On January 12, 2023,
Angel City FC selected Thompson as the first overall pick in the
2023 NWSL Draft. At the time, this trade made Thompson "essentially the most expensive player in league history," which was a record previously set by
Alex Morgan. Thompson signed a three-year deal with the club. Thompson scored five minutes into her professional debut with Angel City FC, in a friendly match against
Club América of
Liga MX Femenil. On April 11, she scored the game-opener against
Portland Thorns FC. She was named
NWSL Rookie of the Month for her performance during March–April 2023. Thompson's third regular season goal was the opening goal in the team's 3–2 win against
Kansas City Current. On June 5, she provided the assist for
Sydney Leroux's first goal and game of the season (after returning from an ankle injury in the previous season). Thompson finished her first season for Angel City with four goals and two assists in regular-season games on the way to the clubs first playoffs appearance, and was also named as one of the nominees for
Rookie of the Year at the conclusion of the season. On May 3, 2024, in Angel City's first game against the
Utah Royals, Thompson made her third assist of the season, and became the youngest player in NWSL history and the first player for Angel City to record assists in three consecutive matches. On May 18, 2024, in an away match against
Washington Spirit, Thompson started alongside her younger sister
Gisele, which marked the first time in NWSL history that two sisters had been named to the starting lineup of the same team. Thompson converted her first penalty kick for Angel City on August 1, 2024, in a shootout against
San Diego Wave FC during the
2024 NWSL x Liga MX Femenil Summer Cup to ensure a spot in the knockout stage of the tournament. Thompson also convereted her first non-shootout penalty for Angel City a few weeks later in a friendly against
Liga MX Femenil team
FC Juárez on August 18, 2024, her first goal of the
2024 season. Thompson scored her first career brace and her first regular-season goals of the 2024 season on August 24, 2024, in an away match against San Diego Wave FC to secure a 1–2 victory. Thompson became the second teenager after
Mallory Swanson to score multiple goals in a regular-season NWSL match. On September 6, 2024, Thompson was named to the
NWSL Team of the Month for the first time for the month of August 2024, playing in three games throughout August, Thompson registered 11 tackles won and six shots, three on target. Thompson notched three goals and one assist throughout September to make the Best XI in back-to-back months. Thompson concluded her sophomore season with a record of 5 goals and 7 assists, securing the second-highest assist total in the league, while also leading Angel City FC in total goal contributions. On January 29, 2025, ahead of the
2025 season, Angel City announced they had signed a contract extension with Thompson, keeping her and her sister at the club until 2028. On April 12, 2025, Thompson made her 50th-regular season appearance in the NWSL, and contributed an assist and a goal in a 3–1 victory against the
Houston Dash, and also became the second-youngest player to reach 10 goals and 10 assists in the NWSL. On May 2, 2025, Thompson assisted her sisters first NWSL goal in a 4–3 victory against
Washington Spirit, and became the first sisters to combine for a goal in the NWSL. On May 24, 2025, Thompson converted her penalty kick against
Racing Louisville FC, to score the 100th regular-season goal in Angel City's history, and with her goal became the all-time leading regular-season goal scorer for Angel City, ultimately the match ended as a 2–3 defeat. The goal was also Thompson's 25th goal contribution in the NWSL regular season, and made her the youngest player to reach the milestone. On July 26, 2025, Thompson scored her first professional hat-trick, in a friendly against
Carolina Ascent FC at BMO Stadium.
Chelsea In September 2025, Thompson entered into talks with English club
Chelsea regarding a potential transfer. On September 5, 2025, it was officially announced that
Chelsea had signed her for a club record fee of just under £1m from Angel City, with the club unveiling her to fans at
Stamford Bridge prior to their first
WSL match of the season against
Manchester City on the same day. Thompson made her debut for Chelsea on September 14 during a 3–1 WSL victory against
Aston Villa. She scored her first goal for the club on October 15, in the Champions League. On March 15, 2026, Thompson won her first trophy with Chelsea after starting in the
2025-26 FA Women's League Cup final in which she helped her team beat
Manchester United 2–0 at
Ashton Gate. ==International career==