Born in Verbania on 4 July 1999, Bonfantini joined Juventus in the summer of 2021. An attacking wide player with great technique and pace to burn, Bonfantini began her career in the youth system at Inter Milano, where she made her Serie B debut at the age of 16. She moved to Roma in 2018, making her Serie A debut and becoming the first player to score a hat-trick for the club in February 2020. Bonfantini was part of the Roma team that won the Coppa Italia in the 2020/21 season.