Tanner Kero was born on July 24, 1992, in Hancock, Michigan. he played four seasons at Michigan Tech before signing as a free agent with the Chicago Blackhawks on April 2, 2015. He would join the Blackhawks' AHL affiliate, the Rockford IceHogs, for six games near the end of the 2014-15 season, in which he scored five goals.
Kero would spend the majority of his first professional season with Rockford, He appeared in 60 games for the club, scoring 20 goals and adding 19 assists. Kero also got his first taste of NHL action during the 2015-16 season, making his NHL debut on October 29, 2015, in a 3–1 loss to the Winnipeg Jets. He would go on to appear in 17 games for the Blackhawks, recording a goal and adding an a pair of assists.
Kero would once again split time between the IceHogs and Blackhawks during the 2016-17 season. In 47 games at the NHL level he scored six times and added 10 assists for 16 points.