???What criteria does a custodial parent have to meet to move a child out of state in Illinois?
I could not find specifics, because it seems to be partially determined by the destination state.
First, the custody agreement has to allow for it. If you have sole custody (no visitation) this would not be an issue, but if visitation is involved, the schedule has to be maintainable in the new location, or the agreement modified.
Second, generally proof of residence and support is needed (i.e. you have a suitable place to stay and sufficient income).
Third, if joint custody is involved, both parties will need to agree to the move.