Carrier performance at one airport
WN→RDU
Southwest Airlines at Raleigh-Durham International
- Departures
- 9,110
- Period
- June 2025 to May 2026
- Routes
- 16
- Rank here
- #3 of 11
Southwest Airlines at Raleigh lands a B, 3 points better than the national rate of 77.4%. About one flight in five arrive 15 minutes late or worse, and those flights are late by about 55 minutes on average. That is a workable record, not a spotless one. That rests on 9,110 flights, of which Delta Air Lines flew 12,085 at 84.4% on time.
Measured against the airport rather than the country, Southwest Airlines runs 2 points ahead of the 78.6% weighted average across all carriers at RDU. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
80.7%
8,961 completed departures
Avg delay
55 min
Across delayed flights only
Cancelled
1.42%
At RDU, this carrier only
Rank here
#3
Of 11 carriers clearing the floor at RDU
These figures cover 9,110 flights between June 2025 and May 2026. The median arrival is 6 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.
Against the competition
Every carrier at RDU, ranked
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 84.4% of the time; PSA Airlines manages 64.9%. Sample sizes sit next to every figure, because a two-point gap across 1,442 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 12,085 | 84.4% | 79 min | 1.59% | B |
| United Airlines | 6,306 | 81.2% | 88 min | 1.17% | B |
| Southwest Airlines (this page) | 9,110 | 80.7% | 55 min | 1.42% | B |
| American Airlines | 9,635 | 79.2% | 96 min | 1.99% | B |
| JetBlue Airways | 2,875 | 77.0% | 76 min | 2.75% | B |
| Republic Airways | 7,834 | 73.7% | 76 min | 4.24% | C− |
| Frontier Airlines | 4,158 | 71.8% | 95 min | 2.91% | C |
| Alaska Airlines | 595 | 71.7% | 44 min | 1.51% | C |
| Envoy Air | 1,103 | 71.5% | 74 min | 3.08% | C− |
| Spirit Airlines | 663 | 67.0% | 79 min | 6.49% | C− |
| PSA Airlines | 1,442 | 64.9% | 78 min | 4.72% | D− |
Spirit Airlines cancels 6.5% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Route by route
Where Southwest Airlines flies from RDU
Southwest Airlines operates 16 routes out of RDU with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| RDU to BWI · Baltimore | 1,790 | 85.2% | 62 min | 2.40% | A |
| RDU to BNA · Nashville | 1,259 | 81.0% | 49 min | 1.03% | B |
| RDU to MDW · Chicago | 1,012 | 80.7% | 54 min | 2.08% | B |
| RDU to MCO · Orlando | 845 | 78.0% | 61 min | 1.66% | B |
| RDU to DEN · Denver | 709 | 73.7% | 57 min | 0.99% | C+ |
| RDU to STL · St. Louis | 648 | 84.7% | 53 min | 0.46% | B+ |
| RDU to AUS · Austin | 512 | 80.1% | 52 min | 0.59% | B+ |
| RDU to DAL · Dallas | 439 | 75.8% | 50 min | 1.14% | B |
| RDU to TPA · Tampa | 382 | 75.5% | 49 min | 1.57% | B |
| RDU to HOU · Houstonthin sample | 354 | 83.4% | 50 min | 0.85% | B+ |
| RDU to LAS · Las Vegasthin sample | 341 | 77.9% | 45 min | 0.59% | B+ |
| RDU to PHX · Phoenixthin sample | 322 | 83.6% | 45 min | 1.24% | B |
| RDU to ATL · Atlantathin sample | 277 | 89.8% | 74 min | 0.72% | A+ |
| RDU to FLL · Fort Lauderdalethin sample | 142 | 76.3% | 58 min | 2.11% | B |
| RDU to MCI · Kansas Citythin sample | 48 | 62.5% | 42 min | 0.00% | D+ |
| RDU to MSY · New Orleansthin sample | 30 | 53.3% | 83 min | 0.00% | F+ |
Departure window
Best time of day for this operation
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 33 points, against 20 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am2,282 flights94.8%
- 8am–11am1,178 flights92.1%
- 11am–2pm1,741 flights85.5%
- 2pm–5pm1,285 flights71.9%
- 5pm–8pm2,060 flights65.3%
- 8pm–5am564 flights62.0%
Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 62.0% on time, against 94.8% 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.
Across the year
Seasonal pattern
July is the worst month at 73.7% on time, 15 points below September, the best at 88.5%. 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.
Delay causes
What holds this operation up
- 53%Late-arriving aircraft
- 23%Carrier
- 21%National Airspace System
- 2%Extreme weather
- 1%Security
53% 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 94,000 reported delay minutes here, that single category outweighs weather by 36 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.
Cancellations sit at 1.42% against a national 1.80%, which is ordinary. Diversions add another 0.22%.
5.3% of arrivals land an hour or more late, close to the national 8.2%. 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 about 55 minutes kind, which a normal layover absorbs.
The sample behind these figures is 9,110 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.
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 88.5% on time and July 73.7%, a swing of 15 points. If the dates move at all, move them out of July before you think about anything else.
Common questions
Southwest Airlines at RDU
How often is Southwest Airlines at RDU delayed?
About one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 19.3% of the 9,110 flights in this analysis, against 22.6% nationally. Delayed flights are late by about 55 minutes on average.
Which airline is most reliable on Southwest Airlines at RDU?
Delta Air Lines leads at 84.4% on time across 12,085 flights. PSA Airlines is at the other end on 64.9%, a gap of 20 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 Southwest Airlines at RDU?
The 5am–8am departure window is the strongest at 94.8% on time. The 8pm–5am window is the weakest at 62.0%, 33 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 July delays on Southwest Airlines at RDU?
July is the weakest month at 73.7% on time, compared with 88.5% in September. Across the year that is 15 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.