Balfour had been in custody on a parole violation since the bodies of Hudson's mother, Darnell Hudson Donerson, and brother, Jason Hudson, were discovered in their home Oct. 24. The body of young Julian King, Balfour's stepson, was found in a sport utility vehicle three days later.
All three had been shot to death.
Until Monday, police had publicly identified Balfour only as a "person of interest" in the investigation.
Balfour's attorney said that he talked to his client Tuesday morning and that he reiterated his innocence.
"It is scary as hell; he's charged with terrible crimes that he adamantly contends he's not guilty of," attorney Joshua Kutnick said before the announcement of the charges, which he said he expected.
Still, Kutnick added, "He's exhibited to me, at least, the patience to let the process unfold."
Police held Balfour for 48 hours after the bodies of Donerson and Hudson were discovered - the longest Chicago police can hold a person without charges. He was then taken by the Illinois Department of Corrections on suspicion that he had violated his parole.
Balfour - the estranged husband of Jennifer Hudson's older sister, Julia Hudson - served seven years for a 1999 attempted murder and vehicular hijacking conviction.
Balfour had refused to take a lie-detector test and stopped cooperating with detectives, according to a police official who was not authorized to discuss the case publicly and spoke on condition of anonymity.
Jennifer Hudson was a finalist in the 2004 season of "American Idol" and won an Academy Award in 2007 for a supporting role in "Dreamgirls." Her publicist, Lisa Kasteler, declined to comment Monday.