Illinois Naturalization Wait Times

N-400 interviews are conducted at **2 field offices** — Chicago (101 W. Congress Parkway) and the Naperville sub-office. Downtown Chicago handles the vast majority of Illinois naturalizations.. Your interview location is determined by your zip code — you can't choose a different office, but it's worth knowing which one you'll visit.

N-400 processing time starts when USCIS accepts the filing and issues a receipt notice. The field office affects interview timing, but the biometrics notice, background checks, request-for-evidence deadlines, and oath ceremony schedule can all add time before citizenship is final.

N-400 processing averages **8–13 months** at the Chicago office (USCIS, Q1 2026). Naperville runs slightly faster at **7–11 months**.. These figures cover the full cycle from receipt to oath ceremony. If your case is straightforward (no name changes, no travel issues, no criminal history), you're likely on the faster end of the range.

Interview scheduling runs **4–6 weeks** before the appointment. The Dirksen Federal Building hosts large oath ceremonies — typically **1,000–2,000** new citizens per event.. After passing the interview, oath ceremonies are typically scheduled within 2–6 weeks — though some offices offer same-day oaths for applicants who pass without conditions.

The naturalization wait time calculator separates receipt, biometrics, interview notice, interview, decision, and oath. That is more useful than one average number because applicants with travel, tax, selective-service, or criminal-history issues may spend more time in review.

Track the receipt date, online-account access code, biometrics appointment, interview notice, interview result, and oath notice. If the case moves outside normal processing time, those dates help decide whether to submit an online inquiry, contact USCIS, or prepare a congressional-service request.

Common delays include missed biometrics, address changes, pending travel, tax payment plans, child-support issues, selective-service questions, name changes, old arrests, and missing certified dispositions. Gather those documents before the interview rather than waiting for a request for evidence.

Start with the current field-office range, then add time for any RFE, rescheduled interview, name-change oath, or administrative review. A clean case may finish near the lower end of the range; a case with missing records or unresolved eligibility questions should use the conservative end of the calculator.