Having joined West Ham from Chelsea last summer in time for the club's maiden professional season, Rafferty helped the team enjoy a respectable WSL campaign and reach a first ever FA Cup final - she played just over an hour of the 3-0 loss at Wembley last week.
Rafferty, who has overcome two ACL injuries during her career, started out her senior career with Millwall Lionesses and made the switch to Chelsea in 2007. She spent 11 years with the club, winning five trophies and establishing herself in the England setup.
Injury limited her number of international caps, but Rafferty was named in World Cup squads in 2011 and 2015 nonetheless, helping the Lionesses finish third in the latter.
"Saturday's game will be my last ever," the player wrote in a statement posted on social media. "I have made the tough decision to retire at the end of the season. I have had a lot of injuries over the years that have taken their toll.
Saturday will be my last game... pic.twitter.com/JwNsrP7D8O— Claire Rafferty (@clrafferty1) May 10, 2019
"Football has brought me so much joy and many incredible opportunities, but most importantly I have made amazing friendships that will last a life time.
"There have been tears and struggles on the way, but having been to two World Cups, one Olympic Games, five FA Cup finals, and won the league three times, I can hold my head up high.
"I hope that I have changed the landscape of the women's game and will continue to fight for equality from a different angle...I hope I have inspired the next generation of girls dreaming of becoming a footballer."
Rafferty also made sure to thank a number of the coaches she has worked with during her career, including Hope Powell, Emma Hayes and Mo Marley, as well as her parents.
Rafferty is the second West Ham player to announce her retirement from football this week after 28-year-old Dutch midfielder Lucienne Reichardt made the difficult decision to walk away from the sport in order to take up a job offer as a psychologist in her native Netherlands.