Cardiff City LFC, 2002–2005 Fishlock started her career playing for
Cardiff City Ladies F.C. and made her debut for the senior side at age 15. Fishlock made her debut against Reading Royals on 29 September 2002 and scored 19 times in 23 appearances in her first season at the club.
Laura McAllister, who was captain of Cardiff City when Fishlock joined the squad said, "Jess joined the junior team but she was so good we fast-tracked her. Jess is just a fabulous player. She is technically superb with fabulous skills and among the 2 or 3% in Britain. She's ambitious and adventurous and to be a top, top sports-player you've got to be like that." At age 16, she was a member of the senior side that won the 2004–05
SW Combination League Championship without losing a point. The team later beat
Everton en route to the last eight of the
FA Cup and won the
Welsh Cup to move on to the
UEFA Women's Cup. As of February 2013, Fishlock remained the club's record goalscorer.
AZ Alkmaar, 2008–2010 , May 2010 In 2008, the Dutch Champions
AZ Alkmaar approached Jess to join them and become the first overseas player in the
Eredivisie. Jess won back to back league titles during the 2008/2009 and 2009/2010 seasons, and was on track for a third straight title during the 2010/2011 season when she left to come back to the UK.
Bristol Academy WFC, 2011–2012 In 2011, Fishlock joined
Bristol in England's
FA Women's Super League (FA WSL). Fishlock was awarded the 2011 Club Player of the Year, 2011 Fans Player of the Year, and was named to the league's All-Star Team. She was named
Welsh Women's Footballer of the Year the same year. During the
2012 season, Bristol achieved their highest final league position, reached the semi-final of the FA Cup and Continental Cup. Jess was awarded the 2012 Club Players Player of Year, 2012 Fans Player of the Year and 2012 FA WSL Players Player of Year, voted on by managers and players of the FA WSL.
Melbourne Victory, 2012–2014 In November 2012, Fishlock joined W-League side
Melbourne Victory for six weeks on a guest player contract helping the team reach their first ever grand final. During the 94th minute of a match against former champions, Canberra United, she scored the game-winning goal boosting Melbourne to the top of the league table. During her six games with Melbourne, she became a favourite with the fans and was also nominated as one of four players for the league-wide Player of the Year Award. In September 2013, it was announced that Fishlock would return to the Victory for the
2013/14 season on loan from the
Seattle Reign FC. During her 11 appearances for the team, she scored three goals and helped lead the team to the Grand Final where the Victory defeated
Brisbane Roar 2–0. Fishlock served an assist to
Lisa De Vanna in the 38th minute for the game-winning goal. She was named Most Valuable Player of the Match. The win marked the Victory's first Grand Final title in the history of the team.
Seattle Reign FC, 2013-2026 , 2013 In February 2013, Fishlock joined
NWSL side
Seattle Reign FC for the league's inaugural season. During their second league match against the
Portland Thorns FC, Fishlock scored her first goal in front of a record-setting 16,479 fans at Jeld-Wen Field, establishing herself as a powerful force for the Reign. The media named her
NWSL Player of the Week for Week 2 of the 2013 season. Fishlock started in all 21 games that she played during the regular season, missing only one game due to Wales national team commitments. She was a leading scorer on the team with four goals and tallied a total of 1,879 minutes. The Reign finished first in the regular season clinching the
NWSL Shield for the first time. After defeating the
Washington Spirit 2–1 in the playoff semi-finals, the Reign were defeated 2–1 by
FC Kansas City during the championship final. Following the regular season, Fishlock along with teammates
Kendall Fletcher,
Kim Little, and
Nahomi Kawasumi was named to the league's Best XI team. Fishlock finished the 2014 season, having scored four goals and provided 8 assists. She started in all 22 matches in which she played. During the
2015 season, Fishlock scored her first goal of the season during the team's home-opener against
Western New York Flash. Her goal in the 25th minute was the first of the match and assist to
Megan Rapinoe in the 86th minute contributed to a 5–1 win for the Reign. During a match against the
Washington Spirit on 2 May, Fishlock scored a goal in the 75th minute off an assist from Kim Little resulting in a 3–1 win over the Spirit. During a match against
Sky Blue FC in New Jersey, Fishlock received a controversial
red card in the 90th minute that required her to sit out the team's next match against league-leading
Chicago Red Stars. The controversy stemmed from a scrum in the box after a Sky Blue
corner kick and Fishlock's last-minute save on the goal line. Fishlock stated the ball bounced off her head, but Sky Blue forward
Nadia Nadim said she blocked it with her hand and the ref awarded Sky Blue the penalty kick. Both matches resulted in 1–1 draws. During the team's second match against Sky Blue FC in Seattle on 6 June, Fishlock scored a goal and an assist earning Player of the Match after leading Seattle to a 3–0 win. She was named NWSL Player of the Week by the media for the ninth week of the season. The Reign finished the regular season in first place clinching the NWSL Shield for the second consecutive time. After advancing to the
playoffs, Seattle faced fourth-place team
Washington Spirit and won 3–0, advancing to the championship final. Seattle was ultimately defeated 1–0 by
FC Kansas City during the championship final in Portland. Fishlock, along with teammates Kim Little,
Beverly Yanez, and
Lauren Barnes were named to the
NWSL Best XI team. During the first few months of the
2016 season, Fishlock was unavailable due to injury along with a number of offensive players, including forwards
Manon Melis and Megan Rapinoe. Seattle finished the regular season in fifth place with a record, narrowly missing a playoff spot by two points. On 24 November 2025, Fishlock signed a new contract with the team, until the end of 2026. She is the only player still with her original team, from when the league launched in 2013. Fishlock scored in a 2–1 win over
Orlando Pride on 15 March 2026, in the Reign's opening game of the
2026 season, which is Fishlock's 13th NWSL season. On 21 April 2026, it was announced that Fishlock would retire at the end of the NWSL season.
Glasgow City loan After the conclusion of the NWSL season in August 2013, it was announced that Fishlock would join
Scottish Women's Premier League champions
Glasgow City on loan until November 2013. Of her signing Glasgow City head coach
Eddie Wolecki Black said, "This signing is significant, not only for the club but also the country. Whilst we continue to set new records at home, our aim is to make progress on the European stage and the signing of Jess highlights this. She will bring experience, versatility, pace and intelligence to the team and most importantly will raise the standard of the players around her. That's what top players do, they make good players better players both on and off the park." She scored two goals in her six appearances for the club helping the club finish in first place during the regular season and win the
Scottish Women's Cup. She also competed in four matches in the
2013–14 UEFA Women's Champions League with the club reaching the Round of 8.
FFC Frankfurt loan , September 2014 Fishlock spent the 2014–15 Seattle Reign FC off-season on loan in the
Frauen-Bundesliga with
FFC Frankfurt. She was a vital part of the team's success, starting in all available matches. Frankfurt was unbeaten in the second half of the season, a run which led them to be crowned the champions of Europe. Although Fishlock returned to Seattle prior to the
2015 UEFA Women's Champions League Final, she was considered a huge part of the team's journey to the championship title by players, staff and fans and subsequently earned a UEFA Women's Champions League medal.
Melbourne City loan Fishlock played on loan for
Melbourne City FC in the Australian
W-League during the
2015-16,
2016-17, and
2017-18 seasons. Fishlock worked as a player-assistant coach during the season. After returning on loan the following season, Fishlock helped the club win the first-ever consecutive W-League titles. During the 2017-18 season, Fishlock was instrumental in City winning its third consecutive championship title and was named Player of the Match.
Reading loan On 19 August 2020, it was confirmed that Fishlock had joined
Reading Women on loan from Seattle Reign FC. The deal was signed as doubts remained about when the NWSL would resume. During a match against Brighton & Hove Albion, she scored two goals lifting Reading to a 3–1 win. ==International career==