Carrier route record
WNORD→PHX
Southwest Airlines · Chicago to Phoenix
- Flights
- 460
- 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 ORD to PHX draws a D. Roughly one flight in two 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 460 flights. The strongest carrier on the route with a full sample, United Airlines, flew 1,938 at 79.1% on time.
The national on-time rate over the same period is 77.6%, so Southwest on ORD to PHX runs 19 points behind the country as a whole. Across a thousand flights that is about 193 extra late arrivals.
Key figures
On time
58.3%
Arrivals under 15 minutes late, of 448 completed flights
Avg delay
67 min
Across delayed arrivals only, not all flights
Cancelled
2.17%
National rate is 1.81%
Whole route
72.9%
Every carrier on ORD to PHX, 5,594 flights
These figures cover 460 flights between July 2025 and June 2026. Beyond the headline rate, 14.1% 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
Southwest against every carrier on ORD to PHX
Southwest flew 460 of the 5,594 flights on ORD to PHX, about 8% of it. Its 58.3% on time is 15 points worse than the route as a whole, which runs 72.9%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from United at 79.1% to Southwest at 58.3%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. United Airlines arrives on time 79.1% of the time; American Airlines manages 71.4%. Sample sizes sit next to every figure, because a two-point gap across 2,993 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 1,938 | 79.1% | 66 min | 0.41% | B+ |
| American Airlines | 2,993 | 71.4% | 84 min | 2.34% | C |
| Frontier Airlinesthin sample | 203 | 67.5% | 82 min | 3.94% | C− |
| Southwest Airlines (this page) | 460 | 58.3% | 67 min | 2.17% | D |
United leads American by 8 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
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 34 points, against 8 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am59 flights81.0%
- 8am–11am31 flights80.6%
- 11am–2pm5 flights—
- 2pm–5pm283 flights53.4%
- 5pm–8pm82 flights46.7%
- 8pm–5am—
Scale runs 40% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 46.7% on time, against 81.0% 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 2pm–5pm window is the busiest, with 283 flights scheduled in it.
Across the year
Southwest on ORD to PHX through the year
July is the worst month at 35.5% on time, 32 points below December, the best at 67.7%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. March was the busiest month here, with 84 flights.
Across the week, Tuesday is the strongest day at 73.4% on time and Friday the weakest at 50.0%. 23 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 56% of the 12,000 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.
- 56%Late-arriving aircraft
- 26%Carrier
- 17%National Airspace System
- 1%Extreme weather
- 0%Security
56% 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 12,000 reported delay minutes here, that single category outweighs weather by 38 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 12,471 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 81.0% on time here.
Cancellations sit at 2.17% against a national 1.81%, which is ordinary. Diversions add another 0.43%.
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. 14.1% 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 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 60.8% on time across 459 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. 460 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 ORD to PHX
Put together: treat all of this as provisional. 460 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 58.3% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 448 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to PHX, every carrier
- Southwest on PHX to ORD, the return leg
- United Airlines on ORD to PHX79.1%
- American Airlines on ORD to PHX71.4%
- Frontier Airlines on ORD to PHX67.5%
- Southwest Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- Phoenix Sky Harbor International (PHX) delay statistics
- Why the first flight of the morning is statistically safest
- How often a connection fails at the major US hubs
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.