All Frontier Message Center mailboxes (Basic, Family, or Deluxe) are based on minute capacity. The total capacity of your mailbox depends upon both how many messages are in your mailbox and the length of the message.
Note: With online voicemail access, you can store important messages indefinitely by saving them onto your computer hard drive.
When you delete a message, it is stored in an erased messages folder, so it's still available if you delete something by accident. You can listen to it or save it in your main mailbox. However, after 7 days in the erased messages folder, the message will be deleted permanently.