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DelayAtlas

Route reliability record

AUSMDW

Austin to Chicago

Flights
1,352
Period
July 2025 to June 2026
Distance
972 mi
Carriers
1
BGRADE

This route lands a B, level with the national rate of 77.6%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by roughly 55 minutes on average. That is a workable record, not a spotless one. That rests on 1,352 AUS to MDW flights, with a median arrival right on schedule.

Best time to fly AUS to MDW: a 5am–8am departure, ideally on a Saturday. Flights in that window arrived on time 91.1% of the time and Saturday flights 82.4%, against 77.5% 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

77.5%

Arrivals under 15 minutes late, of 1,331 completed flights

Avg delay

53 min

Across delayed arrivals only, not all flights

Cancelled

1.26%

National rate is 1.81%

Best carrier

Southwest

77.5% on time across 1,352 flights

These figures cover 1,352 flights between July 2025 and June 2026. On-time means an arrival less than 15 minutes after the scheduled gate time, the same threshold the Department of Transportation uses in its own reports. Cancelled and diverted flights are excluded from the on-time rate and counted separately, which is why the cancellation column matters on its own.

Carrier by carrier

Which airline is most reliable on AUS to MDW

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 AUS to MDW
AirlineFlightsOn timeAvg delayCancelledGrade
Southwest Airlines1,35277.5%53 min1.26%B

Best ways to make this trip

The most reliable ways to fly Austin to Chicago

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. 2 of the top 3 use a different airport at one end.

Most reliable ways to fly from AUS to MDW
OptionAirlineSuccessOn timeCancelledBest departureMost punctual flight
1. AUSMDWAustin to ChicagoSouthwest Airlines76.5%77.5%1.26%5am–8am, Sat
2. AUSORDAustin to ChicagoUnited Airlines74.1%74.9%1.02%5am–8am, TueUA 1878 07:00
3. AUSORDAustin to ChicagoAmerican Airlines67.6%69.8%3.11%8am–11am, WedAA 1726 08:00

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 29 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–8am351 flights91.1%
  • 8am–11am235 flights85.8%
  • 11am–2pm149 flights86.9%
  • 2pm–5pm346 flights62.1%
  • 5pm–8pm121 flights68.3%
  • 8pm–5am150 flights66.7%

Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 91.1% of the time, against 62.1% for the afternoon window. That is 29 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 351 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 28 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 month85J85F60M81A76M64J70J83A89S84O81N79D
Darker means more delays. Figures are on-time percentages.September best, March worst

September is the best month on the calendar at 88.5% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. October was the busiest month here, with 136 flights.

Across the week, Saturday is the strongest day at 82.4% on time and Sunday the weakest at 69.2%. 13 points is a smaller lever than departure hour, but it is free.

On-time rate by day of the week75.2Mon78.2Tue80.3Wed79.5Thu79.4Fri82.4Sat69.2Sun
Monday: 75.2 percent on time. Tuesday: 78.2 percent on time. Wednesday: 80.3 percent on time. Thursday: 79.5 percent on time. Friday: 79.4 percent on time. Saturday: 82.4 percent on time. Sunday: 69.2 percent on time

Delay causes

Why this route gets delayed

One category carries most of the weight here. Late-arriving aircraft accounts for 51% 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
    51%
  • Carrier
    27%
  • National Airspace System
    16%
  • Extreme weather
    5%
  • Security
    1%

51% 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 11 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. The split is drawn from 15,735 reported delay minutes.

The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 91.1% on time here.

Cancellations sit at 1.26% against a national 1.81%, which is ordinary. Diversions add another 0.30%.

Connections and stage length

What a delay here actually costs

6.6% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last roughly 55 minutes, which a normal layover absorbs.

The 972 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 runs 76.3% on time across 1,356 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

The sample behind these figures is 1,352 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.

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

What to do with this

Booking this route

Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 88.5% on time and March 60.2%, a swing of 28 points. If the dates move at all, move them out of March before you think about anything else. 1,331 completed flights over 12 months sit behind that.

Common questions

AUS to MDW questions

How often is AUS to MDW delayed?

Roughly 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 22.5% of the 1,352 flights in this analysis, against 22.4% nationally. Delayed flights are late by roughly 55 minutes on average.

How reliable is AUS to MDW compared with the rest of the country?

77.5% of flights arrive on time here against a national 77.6%, a difference of half a point against it. That is worth a B on this site's grading scale.

What time of day has the fewest delays on AUS to MDW?

The 5am–8am departure window is the strongest at 91.1% on time. The 2pm–5pm window is the weakest at 62.1%, 29 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 AUS to MDW?

March is the weakest month at 60.2% on time, compared with 88.5% in September. Across the year that is 28 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. AUS to MDW and MDW to AUS are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.

Embed AUS to MDW’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.