Release dates are not available in all instances. If federal you can look on the bop.gov website where it is posted. If it is a state sentience, some of them have the information posted on the state DOC website. If you call the facility and ask to speak to the inamte's counselor or case manager, you might get their release date.
https://www.inmateaid.com/ask-the-inmate/how-do-you-find-an-inmate-release-date#answer
Accepted Answer Date Created: February 04,2016