Piper has nominated or won the following awards:
- In 2006, she was nominated for the Young Artist Award for Best Performance in a Feature Film - Young Ensemble Cast, for the 2005 movie Cheaper by the Dozen 2 (This nomination was shared with: Brent Kinsman, Shane Kinsman, Forrest Landis, Liliana Mumy, Kevin Schmidt, Jacob Smith, Alyson Stoner, Blake Woodruff and Morgan York)
- In 2004, she was nominated for Teen Choice Award in the category of Choice Movie Liplock for the 2003 movie Cheaper by the Dozen. Nomination shared with Ashton Kutcher.
- In 2001, she won a MTV Movie Award for Best Music Moment in the 2003 movie Coyote Ugly for Piper singing One Way Or Another. - In 2001, she was nominated for MTV Movie Award in the category Breakthrough Female Performance for 2003 movie Coyote Ugly.
- In 2001, she was nominated Blockbuster Entertainment Award for Favorite Female - Newcomer for the 2000 movie Coyote Ugly.