There is no parole in the federal system. If you are sentenced to prison, you are eligible for fifty-six days good time credit for sentences of more than one year. As an example, if you are sentenced to a ten year sentence then you could get released after 8 years and 4 months. There are several other factors that can also reduce the actual amount of time served in federal prison such as drug treatment programs and the use of half way houses, etc. In addition, federal sentences always include a period of supervised release after a defendant is released from prison.These range from 3 to 5 years and are similar to what is called parole in the state system. If a defendant is on supervised release and violates the terms and conditions of the release, then they can be re-incarcerated for the balance of their time of supervised release.