Sub Accounts are used by a person who has no email address (kids, mostly).

The Sub Account would be under the main account and would use the main accounts email and payment info. The main account would be able to access the sub account's profile to reserve for classes, purchase punch cards or things from the store, etc.

If you have a family member with their own email and want to give separate access, BUT want to link payment info. This can also be done - https://intercom.help/chalk-it-pro/en/articles/9998884-can-i-link-my-payment-account-to-a-family-member-s-profile