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DelayAtlas

Route reliability record

ORDAZO

Chicago to Kalamazoo

Flights
990
Period
July 2025 to June 2026
Distance
122 mi
Carriers
2
C−GRADE

This route carries a cancellation problem, not just a delay problem: 4.2% of scheduled flights never operate, against 1.8% nationally. Of the ones that do fly, close to three flights in four arrive on time, worth a C− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 990 ORD to AZO flights, with a median arrival 5 minutes early.

Best time to fly ORD to AZO: a 8am–11am departure, ideally on a Tuesday. Flights in that window arrived on time 85.7% of the time and Tuesday flights 81.3%, against 74.4% for the route overall.

The US average over the same twelve months is 77.6%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

Key figures

On time

74.4%

Arrivals under 15 minutes late, of 945 completed flights

Avg delay

66 min

Across delayed arrivals only, not all flights

Cancelled

4.24%

National rate is 1.81%

Best carrier

Envoy

75.3% on time across 889 flights

These figures cover 990 flights between July 2025 and June 2026. Beyond the headline rate, 9.0% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Carrier by carrier

Which airline is most reliable on ORD to AZO

Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.

On-time performance by carrier on ORD to AZO
AirlineFlightsOn timeAvg delayCancelledGrade
Envoy Air88975.3%61 min4.16%B−
SkyWest Airlinesthin sample10166.3%97 min4.95%C−

Best ways to make this trip

The most reliable ways to fly Chicago to Kalamazoo

Every airline on this route and on the routes between nearby airports, ranked by how often a scheduled flight actually operated and arrived on time. 4 of the top 5 use a different airport at one end.

Most reliable ways to fly from ORD to AZO
OptionAirlineSuccessOn timeCancelledBest departureMost punctual flight
1. MDWGRRChicago to Grand RapidsSouthwest Airlines74.6%75.2%0.86%8am–11am, Wed
2. ORDGRRChicago to Grand RapidsEnvoy Air73.1%76.1%3.88%5am–8am, Sat
3. ORDGRRChicago to Grand RapidsRepublic Airways72.2%74.5%3.03%2pm–5pm, Thu
4. ORDAZOChicago to KalamazooEnvoy Air72.2%75.3%4.16%8am–11am, Sat
5. ORDGRRChicago to Grand RapidsSkyWest Airlines68.4%70.8%3.46%5am–8am, Fri

Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.

Plan this trip by month, day and time

Departure window

The best time of day to leave

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 23 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

  • 5am–8am
  • 8am–11am279 flights85.7%
  • 11am–2pm106 flights72.3%
  • 2pm–5pm211 flights77.2%
  • 5pm–8pm63 flights62.3%
  • 8pm–5am331 flights66.0%

Scale runs 55% to 90%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 62.3% on time, against 85.7% for the 8am–11am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8pm–5am window is the busiest, with 331 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 31 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.

On-time rate by calendar month67J75F74M74A78M56J61J80A87S80O87N69D
Darker means more delays. Figures are on-time percentages.September best, June worst

June is the worst month at 55.9% on time, 31 points below September, the best at 87.1%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. March was the busiest month here, with 93 flights.

Across the week, Tuesday is the strongest day at 81.3% on time and Sunday the weakest at 68.7%. 13 points is a smaller lever than departure hour, but it is free.

On-time rate by day of the week72.3Mon81.3Tue69.2Wed74.6Thu75.4Fri79.2Sat68.7Sun
Monday: 72.3 percent on time. Tuesday: 81.3 percent on time. Wednesday: 69.2 percent on time. Thursday: 74.6 percent on time. Friday: 75.4 percent on time. Saturday: 79.2 percent on time. Sunday: 68.7 percent on time

Delay causes

Why this route gets delayed

One category carries most of the weight here. Late-arriving aircraft accounts for 50% of the 16,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

  • Late-arriving aircraft
    50%
  • National Airspace System
    18%
  • Extreme weather
    17%
  • Carrier
    15%

Extreme weather accounts for 17% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.8 times the usual weather exposure. The split is drawn from 15,969 reported delay minutes.

50% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 16,000 reported delay minutes here, that single category outweighs weather by 3 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit.

Cancellations run at 4.24%, against 1.81% nationally. That is about one flight in 25 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.

Connections and stage length

What a delay here actually costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.0% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.

At 122 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8am–11am window matters as much as it does.

The return leg is a different operation and performs like one: it runs 79.7% on time across 990 flights, 5 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 5 points of difference.

One caution: this is a thin sample. 990 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

Work out the risk of missing a connection in AZO after this flight

What to do with this

Booking this route

Put together: the delay figures matter less here than the 4.24% cancellation rate. A late arrival costs you about an hour; a cancelled flight costs you the day. Book the 8am–11am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 945 completed flights over 12 months sit behind that.

Common questions

ORD to AZO questions

How often is ORD to AZO delayed?

About one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 25.6% of the 990 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.

How reliable is ORD to AZO compared with the rest of the country?

74.4% of flights arrive on time here against a national 77.6%, a difference of 3 points against it. That is worth a C− on this site's grading scale.

What time of day has the fewest delays on ORD to AZO?

The 8am–11am departure window is the strongest at 85.7% on time. The 5pm–8pm window is the weakest at 62.3%, 23 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.

How bad are June delays on ORD to AZO?

June is the weakest month at 55.9% on time, compared with 87.1% in September. Across the year that is 31 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

Related

Where to go next

Direction matters. ORD to AZO and AZO to ORD are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.

Embed ORD to AZO’s on-time badge on your site

Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.