McCormick and Pearl Jamlead singerEddie Vedder began a relationship in 2000. The couple got engaged in 2009 and married on September 18, 2010. They have two daughters, Olivia and Harper. In 2011, McCormick appeared on the music video for Vedder's solo single, "Longing to Belong". McCormick has adopted her husband's surname as her professional name.
Philanthropy
After quitting modeling, McCormick has turned to activism. She is the co-founder and Vice-Chairman of the EB Research Partnership, a non-profit organization dedicated to finding a cure for the genetic skin disorder Epidermolysis bullosa. McCormick was childhood friends with Ryan Fullmer, whose son, Michael, was born with EB. McCormick along with her husband Eddie Vedder, Ryan Fullmer and his wife Heather, founded Heal EB. In 2014, they merged Heal EB with the Jackson Gabriel Research Foundation to create the EB Research Partnership. The foundation hosts several annual fundraising events and have raised over U$12 million to fund research to find a cure for EB. McCormick is an ambassador for Global Citizen, an organization committed to ending extreme poverty by 2030. She is also active with the Vitalogy Foundation, which supports the efforts of non-profit organizations doing commendable work in the fields of community health, the environment, arts & education and social change. She also supports "Moms Demand Action" on their fight against gun violence and the NRA. Since 2012, McCormick supports "Every Mother Counts", a non-profit that is working to make pregnancy and childbirth safe for every mother in the U.S. and around the world. In 2017 and 2018, McCormick competed in a half-marathon on behalf of Team Every Mother Counts to raise awareness and funds. She is also a supporter of Planned Parenthood. In 2013, along with her sisters Denise and Ashley, Jill formed "Babes Against Brain Cancer", a charity that focuses on helping people with Glioblastoma Multiforme. During a Pearl Jam concert in Milan on June 22, 2018, McCormick wore a jacket that read: "Yes we all care. Y don't u?", in response to the U.S. First Lady Melania Trump, who caused controversy earlier that week when she boarded her plane after visiting children who had been separated from their parents at the border of the United States and Mexico wearing a jacket that read: "I really don’t care. Do u?".