USCIS Chicago field office: address, appointments and the counties it serves

The office at a glance

Which counties go to the Chicago office

USCIS assigns every ZIP code to one field office. In its own data file (August 28, 2026 edition), 628 active ZIP codes in 27 counties are assigned to Chicago: northern Illinois, the Rockford area and four counties of northwest Indiana.

Entirely assigned to this office, 22 counties:

• Boone (IL)
• Carroll (IL)
• Cook (IL)
• DeKalb (IL)
• DuPage (IL)
• Grundy (IL)
• Jo Daviess (IL)
• Kane (IL)
• Kendall (IL)
• La Salle (IL)
• Lake (IL)
• Lee (IL)
• McHenry (IL)
• Ogle (IL)
• Stephenson (IL)
• Whiteside (IL)
• Will (IL)
• Winnebago (IL)
• La Porte (IN)
• Lake (IN)
• Porter (IN)
• St Joseph (IN)

Split ZIP code by ZIP code. Only ZIP codes with a residential area count here; P.O.-box and institutional ZIP codes are listed apart:

• Mostly elsewhereAdams (IL): only 1 of 16 residential ZIP codes go to this office; 15 to Saint Louis. Check your notice.
• Mostly elsewhereBureau (IL): only 1 of 24 residential ZIP codes go to this office; 23 to Des Moines. Check your notice.
• Mostly elsewhereColes (IL): only 1 of 7 residential ZIP codes go to this office; 6 to Saint Louis. Check your notice.
• Mostly elsewhereMacoupin (IL): only 1 of 19 residential ZIP codes go to this office; 18 to Saint Louis. Check your notice.
• P.O. boxes onlySangamon (IL): this office gets only P.O.-box or institutional ZIP codes (3); the county's residential ZIP codes belong to another office.

Three things that send people to the wrong building. Most of central and southern Illinois, including Champaign, Peoria and Springfield, belongs to the St. Louis field office (70 counties): even in Sangamon County, Springfield's street addresses go to St. Louis, and Chicago gets only its three P.O.-box ZIP codes. Rock Island and the Quad Cities area (nine western counties) belong to Des Moines. And Indiana outside those four counties, including Indianapolis and Elkhart, belongs to Indianapolis. Your notice always wins over any list, this one included: USCIS can transfer a case to balance the workload.

Chicago has the third-longest citizenship line in the country

USCIS publishes how many naturalization applications (Form N-400) each office has waiting. On June 30, 2026, Chicago was third of 93 offices.

In USCIS's table (April 1, 2025 to June 30, 2026), Chicago received 5,077 naturalization applications and decided 1,226, approving 946 (77%) against 82% for all offices. For every application it decided, Chicago received 4.1: the line is growing faster here than in Houston (1.1) or Dallas (1.8), and the share approved is below the national figure. That's the office's record, not a forecast for any one case. USCIS accepts the N-400 up to 90 days before you reach the residence requirement. For today's wait, read USCIS's processing-time tool the day you file.

What's confirmed and what's only reported

• OfficialAddress 101 West Ida B. Wells Drive and the counties above. USCIS ZIP data file, Aug 28, 2026.
• OfficialSince May 18, 2026, attorneys and accredited representatives must attend field office interviews in person, except in limited circumstances. Remote participation is over. USCIS field offices page.
• OfficialThe Chicago Asylum Office stopped giving in-person information on April 20, 2026. USCIS asylum office page.
• Official23,623 naturalization applications pending in Chicago on June 30, 2026, third of 93 offices. USCIS N-400 data, FY2026 Q3.

Before your interview

• OfficialYour notice decides. Form I-797C has the address, the time and the documents to bring. The field office, the asylum office and the support centers are different buildings: use the one on your notice.
• OfficialLawyers attend in person. Since May 18, 2026 your attorney or accredited representative can't join by phone or video, except in limited cases. USCIS field offices page.
• OfficialSpanish documents need a certified translation (8 CFR 103.2(b)(3)): how to do it right. An interpreter, if you need one, signs Form G-1256 in front of the officer.
• WarningUSCIS appointments are free: anyone who sells you one is running a scam (report it at 800-375-5283), and a notario can't advise you. If you have no notice and need an appointment, the step-by-step is in the Houston guide.

Biometrics: seven centers, in three states

Fingerprints, photo and signature are taken at Application Support Centers (ASC). USCIS assigns one by ZIP code and prints it on your biometrics notice: you can't choose. The Chicago office uses these, and some are outside Chicago and even outside Illinois:

Bring the notice and a valid photo ID. To reschedule for a good reason, use your USCIS online account at least 12 hours before, or call 800-375-5283. Missing biometrics without rescheduling can get your application denied.

The Chicago Asylum Office is a different building

Affirmative asylum interviews are at 181 W. Madison Street, Suite 3000, Chicago, IL 60602, by appointment only, Monday to Friday, 8 a.m. to 4 p.m. Since April 20, 2026 it gives no in-person information: its USCIS page lists 312-849-5201, and you can email Chicago.Asylum@uscis.dhs.gov. Every ZIP code assigned to the Chicago field office is also assigned to this asylum office. If you're Venezuelan and lost TPS, read why the asylum deadline is running.

Free and low-cost legal help in Chicago

These Chicago organizations are recognized by the Justice Department, so their accredited representatives can represent you before USCIS, like a lawyer, often free or low cost (ask what they charge). From the official roster updated October 18, 2026. It doesn't say which cases each one takes, so call first.

The roster lists many more Chicago organizations than these nine. A representative with full accreditation can appear before an immigration judge; one with partial accreditation (“DHS only”) can represent you before USCIS but not the judge. If your case is in court, read the Chicago immigration court guide and ask who would go with you. In Texas? See Houston.