The 2019 Reign FC season was the club's seventh season of play and their seventh season in the National Women's Soccer League, the top division of women's soccer in the United States. It was the club's first season playing in Tacoma, Washington, following the relocation from Seattle; the 2019 season was also their first under their new name after they were rebranded from Seattle Reign FC.
It was the NWSL's first season with the increased standard roster size from 20 to 22. In addition, there were now four supplemental roster spots for players making the minimum salary that do not count against the team salary cap. Teams were required to carry at least 20 players at any given time and could carry as many as 26 players.
All times are in PT unless otherwise noted.
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|- |colspan="14"|Players who left the club during the season: |-
|- |colspan="14"|Own goals for:
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For transfers in, dates listed are when Reign FC officially signed the players to the roster. Transactions where only the rights to the players are acquired (e.g., draft picks) are not listed. For transfers out, dates listed are when Reign FC officially removed the players from its roster, not when they signed with another club. If a player later signed with another club, her new club will be noted, but the date listed here remains the one when she was officially removed from the Reign FC roster.