Carrier route record

WNRDU→PHX

Southwest Airlines · Raleigh to Phoenix

Flights: 322
Period: July 2025 to June 2026
Share of route: 40%
Carriers: 2

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

Southwest on RDU to PHX lands a B, level with the national rate of 77.6%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 40 minutes on average. That is a workable record, not a spotless one. That rests on 322 flights, with a median arrival 3 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate Southwest on RDU to PHX 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 317 completed flights

Avg delay

41 min

Across delayed arrivals only, not all flights

Cancelled

1.24%

National rate is 1.81%

Whole route

84.0%

Every carrier on RDU to PHX, 811 flights

These figures cover 322 flights between July 2025 and June 2026. The median arrival is 3 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 RDU to PHX

Southwest flew 322 of the 811 flights on RDU to PHX, about 40% of it. Its 78.2% on time is 6 points worse than the route as a whole, which runs 84.0%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from American at 87.8% to Southwest at 78.2%.

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 RDU to PHX
Airline	Flights	On time	Avg delay	Cancelled	Grade
American Airlines	489	87.8%	84 min	0.82%	A+
Southwest Airlines (this page)thin sample	322	78.2%	41 min	1.24%	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 30 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–8am93 flights90.0%
8am–11am45 flights84.1%
11am–2pm102 flights75.5%
2pm–5pm37 flights72.2%
5pm–8pm45 flights60.0%
8pm–5am—

Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 60.0% on time, against 90.0% 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 11am–2pm window is the busiest, with 102 flights scheduled in it.

Across the year

Southwest on RDU to PHX through the year

Jul–Sep 202574 flights95.9%
Oct–Dec 202594 flights80.6%
Jan–Mar 202663 flights81.7%
Apr–Jun 202691 flights59.3%

Scale runs 50% to 100%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 78.2% on time across 322 flights.

Southwest on RDU to PHX did not run the same all year. Its best quarter was Jul–Sep 2025 at 95.9% on time and its weakest Apr–Jun 2026 at 59.3%, a swing of 37 points on roughly 81 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Across the week, Monday is the strongest day at 87.8% on time and Wednesday the weakest at 67.6%. 20 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 54% of the 2,836 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
54%
Carrier
32%
National Airspace System
13%

54% 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 2,836 reported delay minutes here, that single category outweighs weather by 54 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 2,836 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 1.24% against a national 1.81%, which is ordinary. Diversions add another 0.31%.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 3.5% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.

At 1,891 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.

The return leg is a different operation and performs like one: it runs 71.9% on time across 322 flights, 6 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 6 points of difference.

One caution: this is a thin sample. 322 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 RDU to PHX

Put together: treat all of this as provisional. 322 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 78.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 317 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