Illinois N-400 processing: naturalization backlog and denial rate
18,329 naturalization cases were waiting for a decision in Illinois at the end of the quarter, handled by 1 USCIS field office.
How Illinois compares
Illinois has 2.4 quarters of work queued, against 3.8 nationally. That is +1.4 quarters less than the national figure. Among the 46 states with enough decided cases to rate, it ranks 39 for the longest queue, where 1 is the longest.
Its denial rate is 7.4% of cases decided, +3.5 pts against the same quarter a year earlier. Nationally the rate was 11.1%.
Field offices in Illinois
Every USCIS field office in Illinois that decides naturalization cases. The office that handles your case depends on where you live, not on which office is faster. Which office you get is not something you choose, and neither is the queue: the one part of the process you can prepare for is the interview itself, and every official question is in our free US citizenship test practice.
People who became citizens here
In fiscal year 2024, 27,630 people naturalized while living in Illinois, according to the DHS Yearbook of Immigration Statistics. That is a count of people who finished the process, published to the nearest 10, and it is a different measure from the case actions above: it is the latest year DHS has published, and it does not line up quarter for quarter with USCIS case data.
Nearby in the index
- Vermont2.3 quarters queued
- Virginia2.4 quarters queued
- New Mexico2.2 quarters queued
- Pennsylvania2.4 quarters queued
- New York2.5 quarters queued
- Puerto Rico2.1 quarters queued
Sources, data notes and caveats
Where the numbers come from
- USCIS, Number of Form N-400 Applications for Naturalization by Category of Naturalization, Case Status, and USCIS Field OfficeThe nine quarterly workbooks are committed in data/raw/. Direct file URLs are listed per quarter below.
- DHS Office of Homeland Security Statistics, Yearbook of Immigration Statistics, Table 23: Persons Naturalized by State or Territory of ResidencePublished June 2026. Counts are rounded to the nearest 10 by the publisher. This counts people who COMPLETED naturalization and is a different measure from the N-400 case actions above.
- USCIS Historical Processing Times factsheet, FY2016 to FY2024This is a CYCLE-TIME median. USCIS states it is not comparable to the 80th-percentile figures shown on the live processing-times tool. The two must never be plotted on one axis.
- USCIS Case Processing Times toolNOT used as an input to this index. Recorded here because it is the figure most readers arrive with. It publishes only the 80th percentile (80% of cases completed within N months), never a median, and USCIS keeps no public history of it. See scripts/wait-times/ for the forward-looking capture.
- USCIS, 2025 Civics TestN-400 filed before 20 October 2025: 2008 test, up to 10 of 100 questions, 6 to pass. Filed on or after: 2025 test, 20 of 128 questions, 12 to pass.
- USCIS Naturalization Test PerformanceNo per-office or per-state pass rate is published anywhere. No pass-rate data exists yet for the 2025 test version. This index therefore reports no pass rates at office or state level.
What these numbers do and do not mean
- This measures cases, not tests. Nothing here is a civics-test pass rate. USCIS publishes no pass rate by field office or by state, and none is estimated on this page. Most denials turn on eligibility, continuous residence, or good moral character rather than on the test.
- The queue figure is a description of an office, not a prediction about you. It is cases waiting divided by cases decided in the quarter, so it reads as quarters of work already queued at the office's current rate of work. Your own case can be faster or slower for reasons that have nothing to do with the size of the queue.
- Small offices are not rated. Below 200 completed cases in the quarter, a single decision can swing a rate by several points, so we publish the counts and withhold the rate.
- Suppressed cells. USCIS replaces small counts with a “D” to avoid disclosing individuals. We carry those through as unknown, never as zero, which is why a few offices have counts but no rate.
- Two processing-time measures exist and they are not comparable. The USCIS processing-times tool publishes an 80th percentile, meaning 80% of cases finish within that many months. The historical factsheet publishes a median on a different, cycle-time basis. USCIS states these should not be compared. We keep them apart, and neither one feeds the queue figure.
- Pending is not a running total. USCIS states that some case actions are not reflected across reporting periods, so a quarter's pending count cannot be reconstructed by adding receipts to, and subtracting completions from, the quarter before.
- Figures get restated. USCIS revises earlier quarters without notice. Every number here is as published in the workbook listed above, for October 1, 2025 - December 31, 2025.
All sources last verified July 2026. Spot an error? Tell us and we will check it against the source.