Carrier route record

WNMSP→MDW

Southwest Airlines · Minneapolis to Chicago

Flights: 1,608
Period: July 2025 to June 2026
Share of route: 64%
Carriers: 2

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.

Southwest on MSP to MDW lands a B, 2 points better than the national rate of 77.6%. About one flight in five 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 1,608 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 Southwest on MSP to MDW from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

79.1%

Arrivals under 15 minutes late, of 1,576 completed flights

Avg delay

53 min

Across delayed arrivals only, not all flights

Cancelled

1.68%

National rate is 1.81%

Whole route

78.2%

Every carrier on MSP to MDW, 2,499 flights

These figures cover 1,608 flights between July 2025 and June 2026. The median arrival is 5 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

Southwest against every carrier on MSP to MDW

Southwest flew 1,608 of the 2,499 flights on MSP to MDW, most of the route. Its 79.1% on time is about level with the route as a whole at 78.2%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from Southwest at 79.1% to SkyWest at 76.6%.

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 MSP to MDW
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines (this page)	1,608	79.1%	53 min	1.68%	B
SkyWest Airlines	891	76.6%	69 min	1.35%	B

Departure window

When Southwest runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 20 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–8am420 flights90.3%
8am–11am313 flights82.9%
11am–2pm242 flights74.1%
2pm–5pm352 flights73.1%
5pm–8pm265 flights70.8%
8pm–5am16 flights—

Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 90.3% of the time, against 70.8% for the evening window. That is 20 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 420 flights scheduled in it.

Across the year

Southwest on MSP to MDW through the year

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

December is the weak month at 65.4% on time, against 87.7% 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 161 flights.

Across the week, Saturday is the strongest day at 84.5% on time and Sunday the weakest at 74.2%. 10 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Southwest runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 49% of the 17,000 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
49%
Carrier
23%
National Airspace System
23%
Extreme weather
5%
Security
0%

49% 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 17,000 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 17,319 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 90.3% on time here.

Cancellations sit at 1.68% against a national 1.81%, which is ordinary. Diversions add another 0.31%.

Connections and stage length

What a delay here costs

5.1% 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.

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 76.6% on time across 1,594 flights, within 3 points 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 1,608 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 Southwest on MSP to MDW

Put together: the calendar is the biggest lever here, not the carrier or the hour. October runs 87.7% on time and December 65.4%, a swing of 22 points. If the dates move at all, move them out of December before you think about anything else. 1,576 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures