Hi Nancy, no. You can't get in without an appointment in Chicago. Some of the other Passport Agencies are taking walk ins, but not Chicago. I'd advise you to join the group on Facebook called "Passport Appointments" because it's a wealth of information on how to get the appointment to update your passport.
The answer is absolutely NO. I tried and failed. I had to call the congressman and get an emergency appt. I called the appointment line and receive an appointment in El Paso. There are other states you can do walk ups.
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