The bill passed the General Assembly at the end of May.
The bill removes restrictions on both abortions later in pregnancy and criminal penalties for physicians that perform them, repeals both the state's Partial Birth Abortion Ban Act and the Illinois Abortion Act of 1975, and expands insurance coverage for procedures and contraception.
The bill was sponsored by Rep. Kelly Cassidy (D-Chicago), who has said repeatedly that the measure simply codifies existing practices.
Gov. Pritzker has said the act makes Illinois the most progressive state in the nation for reproductive health care. It also came as several other states enacted sweeping abortion bans meant to challenge the 1973 Supreme Court case Roe v. Wade, which legalized abortion at the federal level.
Pritzker will sign the bill at 10 a.m. at the Chicago Cultural Center