Route reliability record

PHX→ORD

Phoenix to Chicago

Flights: 5,593
Period: July 2025 to June 2026
Distance: 1,440 mi
Carriers: 4

This route lands a B, about a point worse than the national rate of 77.6%. About one flight in four arrive 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 5,593 flights, of which American Airlines flew 2,994 at 78.7% on time.

American Airlines is the most reliable of the three carriers covered here at 78.7% on time across 2,994 flights.

On time

76.4%

Arrivals under 15 minutes late, of 5,466 completed flights

Avg delay

78 min

Across delayed arrivals only, not all flights

Cancelled

1.63%

National rate is 1.81%

Best carrier

American

78.7% on time across 2,994 flights

These figures cover 5,593 flights between July 2025 and June 2026. Beyond the headline rate, 8.4% 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

Which airline is most reliable on PHX to ORD

The choice of carrier is not cosmetic here. American Airlines arrives on time 78.7% of the time; Southwest Airlines manages 60.8%. Sample sizes sit next to every figure, because a two-point gap across 459 flights means less than a ten-point one.

On-time performance by carrier on PHX to ORD
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	459	60.8%	67 min	1.31%	D

The spread between American and Southwest is 18 points, wide enough that it should decide the booking. On a hundred trips that is 18 more arrivals inside the on-time window.

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 22 points, against 18 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am1,095 flights90.0%
8am–11am1,150 flights77.5%
11am–2pm1,045 flights73.1%
2pm–5pm1,117 flights67.7%
5pm–8pm679 flights68.3%
8pm–5am507 flights80.9%

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 90.0% of the time, against 67.7% for the afternoon window. That is 22 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 1,150 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 17 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.February best, June worst

June is the worst month at 68.2% on time, 17 points below February, the best at 84.7%. 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 586 flights.

Across the week, Tuesday is the strongest day at 81.3% on time and Monday the weakest at 72.1%. 9 points is a smaller lever than departure hour, but it is free.

Delay causes

Why this route gets delayed

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 101,000 reported delay minutes.

National Airspace System
36%
Late-arriving aircraft
33%
Carrier
28%
Extreme weather
2%
Security
0%

36% 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 37,000 minutes out of 101,000, against a national NAS share of 21%. The split is drawn from 101,234 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 90.0% on time here.

Cancellations sit at 1.63% against a national 1.81%, which is ordinary. Diversions add another 0.64%.

Connections and stage length

What a delay here actually costs

8.4% 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 a little over an hour kind, which a normal layover absorbs.

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 is a different operation and performs like one: it runs 72.9% on time across 5,594 flights, 4 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 4 points of difference.

The sample behind these figures is 5,593 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. February runs 84.7% on time and June 68.2%, a swing of 17 points. If the dates move at all, move them out of June before you think about anything else. 5,466 completed flights over 12 months sit behind that.

Common questions

PHX to ORD questions

How often is PHX to ORD delayed?

About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 23.6% of the 5,593 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.

Which airline is most reliable on PHX to ORD?

American Airlines leads at 78.7% on time across 2,994 flights. Southwest Airlines is at the other end on 60.8%, a gap of 18 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 PHX to ORD?

The 5am–8am departure window is the strongest at 90.0% on time. The 2pm–5pm window is the weakest at 67.7%, 22 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 June delays on PHX to ORD?

June is the weakest month at 68.2% on time, compared with 84.7% in February. Across the year that is 17 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. PHX to ORD and ORD to PHX 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