Carrier performance at one airport
DL→ATL
Delta Air Lines at Hartsfield-Jackson Atlanta International
- Departures
- 240,801
- Period
- July 2025 to June 2026
- Routes
- 25
- Rank here
- #2 of 12
Delta Air Lines at Atlanta lands a B, 2 points better than the national rate of 77.6%. About one flight in five arrive 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 240,801 flights, of which United Airlines flew 7,532 at 80.3% on time.
Measured against the airport rather than the country, Delta Air Lines runs 2 points ahead of the 78.4% weighted average across all carriers at ATL. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
80.0%
236,353 completed departures
Avg delay
59 min
Across delayed flights only
Cancelled
1.60%
At ATL, this carrier only
Rank here
#2
Of 12 carriers clearing the floor at ATL
These figures cover 241,000 flights between July 2025 and June 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 ATL, ranked
The choice of carrier is not cosmetic here. United Airlines arrives on time 80.3% of the time; Frontier Airlines manages 64.5%. Sample sizes sit next to every figure, because a two-point gap across 19,734 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 7,532 | 80.3% | 83 min | 1.47% | B |
| Delta Air Lines (this page) | 240,801 | 80.0% | 59 min | 1.60% | B |
| PSA Airlines | 3,218 | 79.4% | 109 min | 4.72% | B− |
| Alaska Airlines | 1,433 | 77.1% | 56 min | 0.77% | B+ |
| Southwest Airlines | 17,795 | 77.1% | 58 min | 1.15% | B |
| Republic Airways | 2,880 | 77.0% | 78 min | 4.24% | B− |
| American Airlines | 6,810 | 76.4% | 102 min | 2.10% | B |
| SkyWest Airlines | 7,222 | 74.7% | 106 min | 2.26% | C |
| Envoy Air | 1,112 | 73.2% | 69 min | 2.61% | C |
| Spirit Airlines | 5,230 | 71.5% | 75 min | 3.14% | C− |
| JetBlue Airways | 2,575 | 70.7% | 89 min | 3.30% | C− |
| Frontier Airlines | 19,734 | 64.5% | 82 min | 2.15% | D |
PSA Airlines cancels 4.7% 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 Delta Air Lines flies from ATL
Delta Air Lines operates 25 routes out of ATL 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 |
|---|---|---|---|---|---|
| ATL to MCO · Orlando | 5,465 | 70.7% | 64 min | 1.17% | C |
| ATL to LGA · New York | 4,936 | 76.7% | 66 min | 2.96% | B |
| ATL to TPA · Tampa | 4,413 | 74.6% | 55 min | 1.18% | C |
| ATL to FLL · Fort Lauderdale | 4,272 | 73.5% | 55 min | 1.57% | C |
| ATL to LAX · Los Angeles | 3,849 | 79.6% | 55 min | 0.75% | B+ |
| ATL to DCA · Washington | 3,838 | 67.3% | 60 min | 2.58% | C |
| ATL to JAX · Jacksonville | 3,829 | 76.3% | 57 min | 1.44% | B |
| ATL to RDU · Raleigh | 3,799 | 83.2% | 56 min | 1.24% | B |
| ATL to PBI · West Palm Beach | 3,737 | 76.3% | 52 min | 1.53% | B |
| ATL to DTW · Detroit | 3,698 | 79.5% | 57 min | 0.51% | B+ |
| ATL to BOS · Boston | 3,666 | 76.2% | 59 min | 1.72% | B |
| ATL to BNA · Nashville | 3,361 | 82.0% | 56 min | 1.90% | B |
| ATL to LAS · Las Vegas | 3,329 | 77.3% | 55 min | 0.60% | B+ |
| ATL to BHM · Birmingham | 3,306 | 84.0% | 64 min | 1.72% | B |
| ATL to MEM · Memphis | 3,304 | 82.6% | 61 min | 1.85% | B |
| ATL to MIA · Miami | 3,298 | 70.3% | 56 min | 1.43% | C |
| ATL to MSY · New Orleans | 3,275 | 83.2% | 58 min | 1.53% | B |
| ATL to AUS · Austin | 3,233 | 80.2% | 57 min | 1.48% | B |
| ATL to MSP · Minneapolis | 3,221 | 82.1% | 56 min | 0.37% | B+ |
| ATL to CHS · Charleston | 3,210 | 83.7% | 56 min | 1.62% | B |
| ATL to EWR · Newark | 3,055 | 71.5% | 66 min | 3.31% | C− |
| ATL to PHL · Philadelphia | 3,028 | 76.1% | 52 min | 2.48% | B |
| ATL to SAV · Savannah | 3,013 | 83.5% | 53 min | 1.43% | B |
| ATL to SLC · Salt Lake City | 2,959 | 83.0% | 60 min | 0.41% | B+ |
| ATL to BWI · Baltimore | 2,824 | 78.3% | 59 min | 1.95% | B |
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 16 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am10,097 flights89.2%
- 8am–11am51,760 flights87.6%
- 11am–2pm39,382 flights83.6%
- 2pm–5pm45,800 flights77.2%
- 5pm–8pm37,211 flights72.8%
- 8pm–5am56,551 flights76.0%
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 89.2% of the time, against 72.8% for the evening 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 8pm–5am window is the busiest, with 56,551 flights scheduled in it.
Across the year
Seasonal pattern
July is the worst month at 69.8% on time, 17 points below September, the best at 87.2%. 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. July was the busiest month here, with 21,855 flights.
Delay causes
What holds this operation up
- 48%Carrier
- 23%National Airspace System
- 22%Late-arriving aircraft
- 6%Extreme weather
- 0%Security
The largest share of delay minutes, 48%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 1.34 million of the 2.76 million delay minutes reported here. The split is drawn from 2,761,455 reported delay minutes.
Cancellations sit at 1.60% against a national 1.81%, which is ordinary. Diversions add another 0.24%.
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 about an hour kind, which a normal layover absorbs.
240,801 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 87.2% on time and July 69.8%, a swing of 17 points. If the dates move at all, move them out of July before you think about anything else. 236,353 completed flights over 12 months sit behind that.
Common questions
Delta Air Lines at ATL
How often is Delta Air Lines at ATL 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 20.0% of the 240,801 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on Delta Air Lines at ATL?
United Airlines leads at 80.3% on time across 7,532 flights. Frontier Airlines is at the other end on 64.5%, a gap of 16 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 ATL?
The 5am–8am departure window is the strongest at 89.2% on time. The 5pm–8pm window is the weakest at 72.8%, 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 July delays on Delta Air Lines at ATL?
July is the weakest month at 69.8% on time, compared with 87.2% in September. 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.
Related
Where to go next
- Delta Air Lines network-wide record
- Hartsfield-Jackson Atlanta International (ATL) all carriers
- ATL to MCO route record70.7%
- ATL to LGA route record76.7%
- ATL to TPA route record74.6%
- ATL to FLL route record73.5%
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.