Alexis, It appears you can under the conditions described below taken from the P.F. website. Enjoy! *Teenagers ages 15 – 18 can visit any Planet Fitness location in the United States. Teens must work out at the location they sign up at and are not permitted to use other locations. Online signups are not available. Teens under 18 must bring a parent or guardian to sign up.Apr 26, 2019
I would check with the store because I believe with a parent permission waiver they could allow membership for minors. (It's been a few years so rules could have changed.)
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