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DelayAtlas

Route reliability record

OKCORD

Oklahoma City to Chicago

Flights
2,594
Period
July 2025 to June 2026
Distance
693 mi
Carriers
4
BGRADE

This route sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land an hour and a half behind schedule. That rests on 2,594 flights, with a median arrival 5 minutes early.

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

75.1%

Arrivals under 15 minutes late, of 2,511 completed flights

Avg delay

93 min

Across delayed arrivals only, not all flights

Cancelled

2.78%

National rate is 1.81%

Best carrier

SkyWest

73.8% on time across 2,353 flights

These figures cover 2,594 flights between July 2025 and June 2026. Beyond the headline rate, 12.1% 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 OKC to ORD

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 OKC to ORD
AirlineFlightsOn timeAvg delayCancelledGrade
United Airlinesthin sample4100.0%0.00%A+
Envoy Airthin sample2688.0%41 min3.85%A−
Republic Airwaysthin sample21187.9%66 min1.42%A
SkyWest Airlines2,35373.8%94 min2.89%C

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 21 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–8am642 flights80.6%
  • 8am–11am571 flights80.6%
  • 11am–2pm566 flights73.6%
  • 2pm–5pm380 flights77.1%
  • 5pm–8pm435 flights59.6%
  • 8pm–5am

Scale runs 50% to 85%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 59.6% on time, against 80.6% for the 5am–8am 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 5am–8am window is the busiest, with 642 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 14 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 month77J81F68M81A82M74J69J72A81S76O73N68D
Darker means more delays. Figures are on-time percentages.May best, March worst

May is the best month on the calendar at 81.9% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. June was the busiest month here, with 237 flights.

Across the week, Tuesday is the strongest day at 80.6% on time and Sunday the weakest at 65.5%. 15 points is a smaller lever than departure hour, but it is free.

On-time rate by day of the week75.8Mon80.6Tue73.9Wed80.5Thu72.0Fri78.2Sat65.5Sun
Monday: 75.8 percent on time. Tuesday: 80.6 percent on time. Wednesday: 73.9 percent on time. Thursday: 80.5 percent on time. Friday: 72.0 percent on time. Saturday: 78.2 percent on time. Sunday: 65.5 percent on time

Delay causes

Why this route gets delayed

One category carries most of the weight here. Carrier accounts for 54% of the 58,000 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.

  • Carrier
    54%
  • National Airspace System
    22%
  • Late-arriving aircraft
    15%
  • Extreme weather
    9%

The largest share of delay minutes, 54%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 31,000 of the 58,000 delay minutes reported here. The split is drawn from 57,715 reported delay minutes.

Cancellations run at 2.78%, against 1.81% nationally. That is roughly one flight in 40 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. 12.1% 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.

The 693 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg is a different operation and performs like one: it runs 69.3% on time across 2,594 flights, 6 points below 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 6 points of difference.

The sample behind these figures is 2,594 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.

What to do with this

Booking this route

Put together: the calendar is the biggest lever here, not the carrier or the hour. May runs 81.9% on time and March 68.2%, a swing of 14 points. If the dates move at all, move them out of March before you think about anything else. 2,511 completed flights over 12 months sit behind that.

Common questions

OKC to ORD questions

How often is OKC to ORD delayed?

About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 24.9% of the 2,594 flights in this analysis, against 22.4% nationally. Delayed flights are late by an hour and a half on average.

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

75.1% of flights arrive on time here against a national 77.6%, a difference of 3 points against it. That is worth a B on this site's grading scale.

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

The 5am–8am departure window is the strongest at 80.6% on time. The 5pm–8pm window is the weakest at 59.6%, 21 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 March delays on OKC to ORD?

March is the weakest month at 68.2% on time, compared with 81.9% in May. Across the year that is 14 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

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.