Joshua Southwick, Angela Mink and her brother, Ashton Mink, entered pleas Tuesday.
Prosecutors say Ashton Mink's wife, Jacquelin, pleaded guilty last week.
Authorities say Angela and Jacquelin Mink helped the men escape from an Alabama prison in May. Southwick was serving time for murder and burglary; Mink for attempted murder.
The four are believed to have eluded authorities in at least seven states until a June 5 video store robbery in North Dakota. They fled, holed up in a nearby ranch outbuilding and were arrested after shootouts with law enforcement.