Carrier performance at one airport
WN→RDU
Southwest Airlines at Raleigh-Durham International
- Departures
- 8,886
- Period
- September 2025 to August 2026
- Routes
- 15
- Rank here
- #4 of 11
Southwest Airlines at Raleigh lands a B, 3 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That rests on 8,886 flights, of which Delta Air Lines flew 11,943 at 84.7% on time.
Measured against the airport rather than the country, Southwest Airlines runs about a point ahead of the 78.9% 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
79.8%
8,744 completed departures
Avg delay
52 min
Across delayed flights only
Cancelled
1.29%
At RDU, this carrier only
Rank here
#4
Of 11 carriers clearing the floor at RDU
These figures cover 8,886 flights between September 2025 and August 2026. The median arrival is 5 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 84.7% of the time; PSA Airlines manages 63.9%. Sample sizes sit next to every figure, because a two-point gap across 1,695 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 11,943 | 84.7% | 80 min | 1.72% | B |
| United Airlines | 6,220 | 81.3% | 93 min | 1.29% | B |
| American Airlines | 9,463 | 80.6% | 97 min | 1.89% | B |
| Southwest Airlines (this page) | 8,886 | 79.8% | 52 min | 1.29% | B |
| Alaska Airlines | 686 | 75.8% | 51 min | 1.02% | B |
| JetBlue Airways | 3,064 | 75.5% | 80 min | 4.14% | B− |
| Republic Airways | 7,491 | 74.4% | 76 min | 4.34% | C− |
| Frontier Airlines | 4,324 | 73.4% | 93 min | 2.52% | C |
| Envoy Air | 1,135 | 71.3% | 77 min | 3.00% | C |
| Spirit Airlines | 405 | 64.2% | 75 min | 7.65% | D− |
| PSA Airlines | 1,695 | 63.9% | 95 min | 6.90% | D− |
Spirit Airlines cancels 7.7% 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 15 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 | 1,763 | 85.8% | 56 min | 2.21% | A |
| RDU to BNA · Nashville | 1,266 | 80.4% | 48 min | 1.03% | B |
| RDU to MDW · Chicago | 960 | 77.3% | 54 min | 1.77% | B |
| RDU to MCO · Orlando | 841 | 79.3% | 63 min | 1.31% | B |
| RDU to DEN · Denver | 710 | 74.8% | 55 min | 0.99% | C+ |
| RDU to STL · St. Louis | 664 | 80.4% | 54 min | 0.30% | B+ |
| RDU to AUS · Austin | 533 | 77.8% | 54 min | 0.38% | B+ |
| RDU to DAL · Dallas | 417 | 76.2% | 53 min | 1.20% | B |
| RDU to TPA · Tampa | 383 | 80.6% | 47 min | 1.57% | B |
| RDU to HOU · Houstonthin sample | 354 | 80.9% | 41 min | 0.85% | B+ |
| RDU to PHX · Phoenixthin sample | 322 | 72.6% | 39 min | 0.93% | C+ |
| RDU to LAS · Las Vegasthin sample | 282 | 76.1% | 42 min | 0.71% | B+ |
| RDU to ATL · Atlantathin sample | 185 | 90.2% | 62 min | 1.08% | A |
| RDU to FLL · Fort Lauderdalethin sample | 142 | 76.3% | 62 min | 2.11% | B |
| RDU to MCI · Kansas Citythin sample | 47 | 55.3% | 44 min | 0.00% | D+ |
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 35 points, against 21 points between the best and worst carrier.
- 5am–8am2,248 flights94.8%
- 8am–11am1,170 flights91.2%
- 11am–2pm1,775 flights82.5%
- 2pm–5pm1,177 flights69.3%
- 5pm–8pm2,001 flights65.0%
- 8pm–5am515 flights60.1%
Scale runs 50% to 100%.
The 8pm–5am window is where this operation falls apart: 60.1% 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. The 5am–8am window is the busiest, with 2,248 flights scheduled in it.
Across the year
Seasonal pattern
June is the worst month at 70.7% on time, 18 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. December was the busiest month here, with 846 flights.
Delay causes
What holds this operation up
- 53%Late-arriving aircraft
- 25%Carrier
- 18%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. Across 92,000 reported delay minutes here, that single category outweighs weather by 25 to one. The split is drawn from 91,912 reported delay minutes.
Cancellations sit at 1.29% against a national 1.89%, which is ordinary. Diversions add another 0.30%.
5.1% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last roughly 50 minutes, which a normal layover absorbs.
The sample behind these figures is 8,886 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 June 70.7%, a swing of 18 points. If the dates move at all, move them out of June before you think about anything else. 8,744 completed flights over 12 months sit behind that.
Common questions
Southwest Airlines at RDU
How often is Southwest Airlines at RDU delayed?
About one flight in five arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 20.2% of the 8,886 flights in this analysis, against 22.7% nationally. Delayed flights are late by roughly 50 minutes on average.
Which airline is most reliable on Southwest Airlines at RDU?
Delta Air Lines leads at 84.7% on time across 11,943 flights. PSA Airlines is at the other end on 63.9%, a gap of 21 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 60.1%, 35 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 Southwest Airlines at RDU?
June is the weakest month at 70.7% on time, compared with 88.5% in September. Across the year that is 18 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, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.