Route reliability record

MSP→MDW

Minneapolis to Chicago

Flights: 2,499
Period: July 2025 to June 2026
Distance: 349 mi
Carriers: 2

This route lands a B, level with the national rate of 77.6%. Roughly one flight in five arrive 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 2,499 flights, of which Southwest Airlines flew 1,608 at 79.1% on time.

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.

On time

78.2%

Arrivals under 15 minutes late, of 2,452 completed flights

Avg delay

59 min

Across delayed arrivals only, not all flights

Cancelled

1.56%

National rate is 1.81%

Best carrier

Southwest

79.1% on time across 1,608 flights

These figures cover 2,499 flights between July 2025 and June 2026. The median arrival is 4 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.

Carrier by carrier

Which airline is most reliable on MSP to MDW

The two carriers here are closely matched: 3 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.

On-time performance by carrier on MSP to MDW
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines	1,608	79.1%	53 min	1.68%	B
SkyWest Airlines	891	76.6%	69 min	1.35%	B

No carrier stands out. Southwest tops the table at 79.1%, 3 points clear of the bottom, which is inside the range this kind of sample moves year to year.

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 17 points, against 3 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am696 flights86.1%
8am–11am347 flights82.2%
11am–2pm516 flights76.8%
2pm–5pm560 flights73.8%
5pm–8pm364 flights68.8%
8pm–5am16 flights—

Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 86.1% of the time, against 68.8% for the evening window. That is 17 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 696 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 27 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.

Darker means more delays. Figures are on-time percentages.October best, December worst

December is the weak month at 62.4% on time, against 89.8% in October. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. July was the busiest month here, with 249 flights.

Across the week, Saturday is the strongest day at 81.8% on time and Sunday the weakest at 73.6%. 8 points is a smaller lever than departure hour, but it is free.

Delay causes

Why this route gets delayed

One category carries most of the weight here. Carrier accounts for 44% of the 31,000 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
44%
Late-arriving aircraft
27%
National Airspace System
17%
Extreme weather
11%
Security
0%

Extreme weather accounts for 11% 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 1.8 times the usual weather exposure. The split is drawn from 31,435 reported delay minutes.

The largest share of delay minutes, 44%, 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 14,000 of the 31,000 delay minutes reported here.

Cancellations sit at 1.56% against a national 1.81%, which is ordinary. Diversions add another 0.32%.

Connections and stage length

What a delay here actually costs

6.3% 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 are the about an hour kind, which a normal layover absorbs.

At 349 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 5am–8am window matters as much as it does.

The return leg runs 76.9% on time across 2,485 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 2,499 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. October runs 89.8% on time and December 62.4%, a swing of 27 points. If the dates move at all, move them out of December before you think about anything else. 2,452 completed flights over 12 months sit behind that.

Common questions

MSP to MDW questions

How often is MSP to MDW delayed?

Roughly one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 21.8% of the 2,499 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.

Which airline is most reliable on MSP to MDW?

Southwest Airlines leads at 79.1% on time across 1,608 flights. SkyWest Airlines is at the other end on 76.6%, a gap of 3 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.

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

The 5am–8am departure window is the strongest at 86.1% on time. The 5pm–8pm window is the weakest at 68.8%, 17 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 December delays on MSP to MDW?

December is the weakest month at 62.4% on time, compared with 89.8% in October. Across the year that is 27 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

Where to go next

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

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

Key figures