Carrier performance at one airport
DL→RDU
Delta Air Lines at Raleigh-Durham International
- Departures
- 12,031
- Period
- July 2025 to June 2026
- Routes
- 13
- Rank here
- #1 of 11
Delta Air Lines at Raleigh earns a A. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 12,031 flights, of which Delta Air Lines flew 12,031 at 85.1% on time.
Measured against the airport rather than the country, Delta Air Lines runs 6 points 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
85.1%
11,819 completed departures
Avg delay
80 min
Across delayed flights only
Cancelled
1.63%
At RDU, this carrier only
Rank here
#1
Of 11 carriers clearing the floor at RDU
These figures cover 12,000 flights between July 2025 and June 2026. The median arrival is 10 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 85.1% of the time; Spirit Airlines manages 64.6%. Sample sizes sit next to every figure, because a two-point gap across 578 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines (this page) | 12,031 | 85.1% | 80 min | 1.63% | A |
| United Airlines | 6,263 | 81.1% | 87 min | 1.23% | B |
| Southwest Airlines | 9,026 | 80.4% | 54 min | 1.38% | B |
| American Airlines | 9,574 | 79.7% | 96 min | 2.06% | B |
| JetBlue Airways | 2,908 | 76.9% | 78 min | 2.89% | B |
| Republic Airways | 7,682 | 74.3% | 75 min | 4.13% | C− |
| Frontier Airlines | 4,205 | 73.1% | 93 min | 2.59% | C |
| Alaska Airlines | 625 | 72.6% | 46 min | 1.60% | C |
| Envoy Air | 1,090 | 70.9% | 75 min | 3.30% | C− |
| PSA Airlines | 1,528 | 65.4% | 77 min | 5.24% | C− |
| Spirit Airlines | 578 | 64.6% | 81 min | 6.23% | D− |
Spirit Airlines cancels 6.2% 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 Delta Air Lines flies from RDU
Delta Air Lines operates 13 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 ATL · Atlanta | 3,800 | 89.5% | 86 min | 1.37% | A |
| RDU to BOS · Boston | 1,436 | 80.4% | 87 min | 2.51% | B |
| RDU to DTW · Detroit | 1,337 | 88.0% | 82 min | 1.20% | A |
| RDU to MSP · Minneapolis | 1,227 | 84.1% | 73 min | 1.22% | B |
| RDU to MCO · Orlando | 1,005 | 81.9% | 80 min | 2.39% | B |
| RDU to TPA · Tampa | 649 | 84.3% | 79 min | 1.85% | B |
| RDU to SLC · Salt Lake City | 412 | 82.8% | 66 min | 1.21% | B |
| RDU to LAX · Los Angeles | 383 | 84.5% | 75 min | 0.78% | B+ |
| RDU to SEA · Seattlethin sample | 364 | 83.1% | 49 min | 1.37% | B |
| RDU to FLL · Fort Lauderdalethin sample | 364 | 78.8% | 65 min | 1.10% | B |
| RDU to MIA · Miamithin sample | 360 | 80.5% | 82 min | 1.67% | B |
| RDU to LGA · New Yorkthin sample | 344 | 72.7% | 95 min | 4.07% | C− |
| RDU to LAS · Las Vegasthin sample | 333 | 90.3% | 48 min | 0.90% | A+ |
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 16 points, against 21 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am3,817 flights90.4%
- 8am–11am1,700 flights89.2%
- 11am–2pm2,653 flights82.9%
- 2pm–5pm1,094 flights82.1%
- 5pm–8pm2,398 flights79.1%
- 8pm–5am369 flights74.8%
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 90.4% of the time, against 74.8% for the overnight window. That is 16 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 3,817 flights scheduled in it.
Across the year
Seasonal pattern
December is the weak month at 77.5% on time, against 90.1% in September. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. October was the busiest month here, with 1,109 flights.
Delay causes
What holds this operation up
- 37%Carrier
- 35%Late-arriving aircraft
- 26%National Airspace System
- 2%Extreme weather
35% 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 140,000 reported delay minutes here, that single category outweighs weather by 22 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 139,959 reported delay minutes.
Cancellations sit at 1.63% against a national 1.81%, which is ordinary. Diversions add another 0.13%.
6.1% 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.
12,031 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 90.1% on time and December 77.5%, a swing of 13 points. If the dates move at all, move them out of December before you think about anything else. 11,819 completed flights over 12 months sit behind that.
Common questions
Delta Air Lines at RDU
How often is Delta Air Lines at RDU delayed?
About one flight in seven arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 14.9% of the 12,031 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 Delta Air Lines at RDU?
Delta Air Lines leads at 85.1% on time across 12,031 flights. Spirit Airlines is at the other end on 64.6%, 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 Delta Air Lines at RDU?
The 5am–8am departure window is the strongest at 90.4% on time. The 8pm–5am window is the weakest at 74.8%, 16 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 December delays on Delta Air Lines at RDU?
December is the weakest month at 77.5% on time, compared with 90.1% in September. Across the year that is 13 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, July 2025 to June 2026. Updated monthly. How this data is collected.