Carrier route record
WNPHX→ORD
Southwest Airlines · Phoenix to Chicago
- Flights
- 459
- Period
- July 2025 to June 2026
- Share of route
- 8%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on PHX to ORD draws a D. Roughly one flight in three arrives at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 459 flights. The strongest carrier on the route with a full sample, American Airlines, flew 2,994 at 78.7% on time.
The national on-time rate over the same period is 77.6%, so Southwest on PHX to ORD runs 17 points behind the country as a whole. Across a thousand flights that is about 168 extra late arrivals.
Key figures
On time
60.8%
Arrivals under 15 minutes late, of 449 completed flights
Avg delay
67 min
Across delayed arrivals only, not all flights
Cancelled
1.31%
National rate is 1.81%
Whole route
76.4%
Every carrier on PHX to ORD, 5,593 flights
These figures cover 459 flights between July 2025 and June 2026. Beyond the headline rate, 14.5% 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
Southwest against every carrier on PHX to ORD
Southwest flew 459 of the 5,593 flights on PHX to ORD, about 8% of it. Its 60.8% on time is 16 points worse than the route as a whole, which runs 76.4%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from American at 78.7% to Southwest at 60.8%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: about a point 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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| American Airlines | 2,994 | 78.7% | 75 min | 2.24% | B |
| United Airlines | 1,937 | 77.3% | 82 min | 0.52% | B+ |
| Frontier Airlinesthin sample | 203 | 68.8% | 122 min | 3.94% | C− |
| Southwest Airlines (this page) | 459 | 60.8% | 67 min | 1.31% | D |
No carrier stands out. American tops the table at 78.7%, about a point clear of the bottom, which is inside the range this kind of sample moves year to year.
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 26 points, against about a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am27 flights—
- 8am–11am125 flights71.5%
- 11am–2pm110 flights45.4%
- 2pm–5pm82 flights66.2%
- 5pm–8pm115 flights56.6%
- 8pm–5am—
Scale runs 35% to 75%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 45.4% on time against 71.5% for 8am–11am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 8am–11am window is the busiest, with 125 flights scheduled in it.
Across the year
Southwest on PHX to ORD through the year
Delays peak in May, when the on-time rate falls to 50.0%. January is the strongest month at 80.0%. Moving a flexible trip across that boundary buys 30 points. March was the busiest month here, with 85 flights.
Across the week, Saturday is the strongest day at 70.3% on time and Monday the weakest at 46.2%. 24 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Southwest runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 12,000 reported delay minutes.
- 40%National Airspace System
- 32%Carrier
- 27%Late-arriving aircraft
- 1%Security
40% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 4,680 minutes out of 12,000, against a national NAS share of 21%. The split is drawn from 11,744 reported delay minutes.
Cancellations sit at 1.31% against a national 1.81%, which is ordinary. Diversions add another 0.87%.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 14.5% 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 1,440 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 58.3% on time across 460 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.
One caution: this is a thin sample. 459 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.
What to do with this
Booking Southwest on PHX to ORD
Put together: treat all of this as provisional. 459 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 60.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 449 completed flights over 12 months sit behind that.
Related
Where to go next
- PHX to ORD, every carrier
- Southwest on ORD to PHX, the return leg
- American Airlines on PHX to ORD78.7%
- United Airlines on PHX to ORD77.3%
- Frontier Airlines on PHX to ORD68.8%
- Southwest Airlines network-wide record
- Phoenix Sky Harbor International (PHX) delay statistics
- Chicago O'Hare International (ORD) delay statistics
- How often a connection fails at the major US hubs
- The best time of day to fly, according to 7.04 million flight records
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.