In November 2013, FC Kansas City traded Mewis to Seattle Reign FC for Amy Rodriguez.[20] Of the trade, Reign FC coach, Laura Harvey said, "Kristie is a young, bright and talented player who we feel can benefit our long-term plan. She has proven that she can be a high-level player in this environment and we feel we have the structure to help push Kristie to the next level."[21] On November 18, 2013, she was traded alongside Michelle Betos and two 2015 NWSL College Draft picks to the Boston Breakers for Sydney Leroux.[22]