Phones are usually turned on at 6am and are turned off at 9:30pm. There may also be times during the day where there is no access to them - the rules inside every facility change without notice and the inmates have to deal with the inconsistencies.
https://www.inmateaid.com/ask-the-inmate/at-stillwater-farm-mn-prison-what-are-the-hours-an-cost-that-u-can-use-the-phone#answer
Accepted Answer Date Created: March 27,2013