 Prior to turning professional, Tkachuk played one season for the Boston University Terriers, earning All-Hockey East Rookie Team honors.Internationally, Tkachuk has represented Team USA at the 2017 IIHF World U18 Championships and 2018 World Junior Ice Hockey Championships.After playing for the St. Louis AAA Blues U16 and committing to the USA Hockey National Team Development Program (USNDPT), Tkachuk agreed to play for Boston University after completing two seasons with the USNDPT.