The Minneapolis Star-Tribune reported that Mauer has bought a full-page advertisement for Sunday's editions that informs fans of his decision.
"After much consideration I have decided to retire from playing baseball," the ad from Mauer says, according to the Star-Tribune. "The decision came down to my health and my family. The risk of concussion is always there, and I was reminded of that this season after missing over 30 games as a result of diving for a foul ball.
"Thank you, Minnesota Twins, and thank you, fans, for making my career as special and memorable as it was. Because of you I can leave the game I love with a full and grateful heart."
The three-time American League batting champion — the only catcher to ever win three batting titles — would have been a free agent after his eight-year, $184 million contract expired at the end of the 2018 season.
In addition to the concussion suffered this past season, Mauer also suffered one in 2013, which facilitated his move from catcher to first base.
Mauer, 35, had stated that he had no interest in playing outside of his home state.
The six-time All-Star selection will finish his career with a .306 batting average with 143 home runs and 923 RBIs. Mauer is the Twins' all-time leader in times on base, passing Hall of Fame member Harmon Killebrew.
Mauer, who was selected by the Twins with the first overall selection in the 2001 draft, also won three Gold Glove awards and five Silver Sluggers during his career.