Explanation of Residency Requirements:

You or your spouse must meet the residency requirement in order to file for divorce in Illinois. Under Illinois law, either you or your spouse must have resided in the state of Illinois for at least 90 days prior to filing the Petition for Dissolution of Marriage. The divorce should be filed in the Circuit Court of the county where either spouse resides.
You are considered a resident of Illinois if you physically live in the state and intend to make Illinois your permanent home. Indicators of residency may include where you primarily live, receive mail, sleep at night, the address listed on your driver’s license or state ID, or the address used on your federal or state tax returns.
If you or your spouse is a member of the military, you may still file for divorce in Illinois if either of you has maintained residency in Illinois for at least 90 days, regardless of where you are currently stationed. Military members who claim Illinois as their state of legal residence and have maintained sufficient ties to Illinois may meet this requirement, even if deployed or temporarily living elsewhere.‍