Chicago’s traffic and speed enforcement cameras produce a by-product that gets almost no attention: a count of passing traffic. The city’s transportation department publishes that count as a data feed that has accumulated 2.2 million daily readings since July 2022 and is refreshed every day; 2,280 quarter-to-half-mile street segments carried readings in this June and July alone. It is a continuously updated, segment-level record of street traffic — with the limits of camera-derived counting, which we detail below — and this analysis reads it in full. The headline finding is how little is changing: across the 1,572 segments measured in both early summer 2025 and early summer 2026, the median segment moved -0.4 percent — 768 segments up, 800 down, and 4 recorded exactly no change. Push the comparison back to 2023 on the 944 segments measured in both years and the median change is 0 percent. On the streets these cameras measure, traffic is running almost exactly at last year’s level for the median matched segment — and at 2023’s — even as a minority of segments swung hard in both directions.
The busiest streets, counted around the clock
The single busiest measured stretch in the city is Ontario Street westbound between La Salle Drive and Orleans Street, at 33,466 vehicles a day this June and July. But the street that owns the leaderboard is Cicero Avenue: 4 of the ten busiest segments are on it, clustered between 45th and 50th Streets, each carrying roughly 29,000 to 32,000 vehicles a day in the counter’s reading. Stony Island Avenue at 95th Street, 99th Street at Halsted, and stretches of Ohio and Orleans Streets adjoining the Ontario segment complete the ten. A note on what these numbers are: each daily reading in the feed is itself a trailing 30-day average, so a segment’s figure describes its recent typical day, not any single afternoon.
The typical street barely moved
Of the 1,572 matched segments, 484 sit within five percent of last year’s reading and 1,143 within twenty. That stability is the story. Our Divvy analysis found bike-share trips far above their pre-pandemic level and our transit hub tracks a bus and rail system still short of its 2015 peak — but on the median matched segment, the car traffic these cameras watch is holding remarkably steady. The feed cannot say why, and neither will we; what it can say is that on the same stretches of the same streets, measured the same way in the same weeks of the year, the typical segment’s number hardly changed — while a minority of segments, covered next, swung hard in both directions.
The big swings are flags, not trends
The tails of that chart deserve suspicion rather than headlines. When a segment’s recorded count falls by three-quarters or multiplies by seven in a year, possible explanations include a construction closure, a detour that rerouted traffic, a camera moved or offline, a change in how the vendor’s counting software reads the scene — or a real shift in traffic. The data does not say which. The portal itself notes that counts can be wrong under unexpected device or field conditions and that accuracy is higher from May 2026 onward. So we present the largest recorded one-year swings as exactly that — recorded swings, with no claim about what caused them. Percentages are computed from unrounded daily averages, so they can differ by a tenth of a point from the rounded counts shown:
The five largest recorded declines among matched segments:
- Halsted NB from N North Branch St to W Division St: 11,049 to 1,803 vehicles a day (-83.7%)
- Halsted SB from W Division St to N North Branch St: 8,646 to 1,622 vehicles a day (-81.2%)
- Irving Park EB from N Normandy Ave to N Narragansett Ave: 11,404 to 2,991 vehicles a day (-73.8%)
- 71st EB from S Dorchester Ave to S Stony Island Ave: 17,588 to 4,722 vehicles a day (-73.1%)
- North WB from N Clark St to N Wells St: 14,306 to 4,128 vehicles a day (-71.1%)
And the five largest recorded increases:
- Lincoln Southeast from N McCormick Rd to W Peterson Ave: 2,012 to 16,785 vehicles a day (+734.1%)
- Lincoln Northwest from N McCormick Rd to W Devon Ave: 2,012 to 14,211 vehicles a day (+606.2%)
- Archer Northeast from S Damen Ave to S Wood St: 1,134 to 7,935 vehicles a day (+599.8%)
- Ogden Northeast from S Western Ave to W Taylor St: 1,332 to 8,951 vehicles a day (+571.8%)
- 103rd WB from S Crandon Ave to S Doty Ave: 1,789 to 11,778 vehicles a day (+558.4%)
Look up your street
How we counted
- Source: City of Chicago Average Daily Traffic Counts (gc7y-n4xa), pulled August 3, 2026; 2,224,055 daily records from July 28, 2022 through August 3, 2026. Counts are a by-product of the city’s 800-plus traffic and speed enforcement cameras: vendors count vehicles from video and radar with proprietary algorithms, and CDOT’s traffic-management system assigns each camera’s count to its street segment.
- The unit: each daily record is a trailing 30-day average for one segment, as published; we did not un-smooth it. Segment figures here are the average of those daily values across June 1 – July 31 of the named year.
- Matching: comparisons use only segments with readings on at least 45 of the 61 window days in both years — 1,572 segments for 2025-vs-2026 and 944 for 2023-vs-2026. The camera network grew from 1,260 measured segments in 2022 to 2,378 in 2026, so unmatched comparisons would mostly measure where cameras were added, not how traffic changed.
- Known limits: the portal states that counts can be inaccurate under unexpected device or field conditions, that corrections may appear only after the fact, and that accuracy and consistency are higher from May 2026 and later — which means the earlier side of every comparison here rests on the less-consistent vintage. These are camera-derived estimates, not physical axle counts.
- What this is not: a measure of speeds, congestion, or why any count changed. It is what the city’s published feed recorded.
Computed by KCM Desk from records current to August 3, 2026; published August 3, 2026. If you spot an error, corrections come first.