If the inmate is in state or federal, there is a system they can check to see if their funds have arrived on their books.
https://www.inmateaid.com/ask-the-inmate/are-the-inmates-notified-if-a-phone-call-account-has-money-available-on-it-so-that-they-can-make-calls-i-set-up-an-account-for-my-nephew-but-how-will-he-know-that-there-is-money-on-the-account-so-that-he-can-call-family#answer
Accepted Answer Date Created: November 16,2017