Atlanta, GA · departure reliability
ATL
Hartsfield-Jackson Atlanta International
- Departures
- 315,727
- Period
- September 2025 to August 2026
- Carriers
- 12
- US rank
- #3 by volume
Atlanta
Hartsfield-Jackson Atlanta International lands a B, level with the national rate of 77.3%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That rests on 315,727 flights, of which United Airlines flew 7,672 at 79.7% on time.
United Airlines is the most reliable of the twelve carriers covered here at 79.7% on time across 7,672 flights.
Key figures
On time
77.9%
Departures arriving under 15 minutes late at their destination
Avg delay
66 min
Across delayed flights only
Cancelled
1.83%
National rate is 1.89%
Best carrier
United
79.7% on time here
These figures cover 316,000 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.
Carrier by carrier
Which airlines run best out of ATL
The choice of carrier is not cosmetic here. United Airlines arrives on time 79.7% of the time; Frontier Airlines manages 63.7%. Sample sizes sit next to every figure, because a two-point gap across 20,778 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 240,917 | 79.5% | 59 min | 1.67% | B |
| Frontier Airlines | 20,778 | 63.7% | 83 min | 2.42% | D |
| Southwest Airlines | 17,133 | 76.4% | 59 min | 1.10% | B |
| United Airlines | 7,672 | 79.7% | 84 min | 1.51% | B |
| American Airlines | 6,907 | 75.7% | 106 min | 1.90% | B |
| SkyWest Airlines | 6,699 | 75.1% | 106 min | 2.58% | B |
| Spirit Airlines | 3,886 | 70.7% | 77 min | 4.01% | C− |
| PSA Airlines | 3,319 | 77.6% | 110 min | 5.33% | B− |
| Republic Airways | 3,135 | 74.9% | 84 min | 4.85% | C− |
| JetBlue Airways | 2,858 | 69.1% | 89 min | 4.55% | C− |
| Alaska Airlines | 1,359 | 78.7% | 54 min | 0.81% | B+ |
| Envoy Air | 1,064 | 72.1% | 69 min | 2.54% | C |
PSA Airlines cancels 5.3% 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
Busiest routes out of ATL
Route-level records vary far more than the airport average. These are the 25 busiest departures from ATL, each with its own on-time rate against the airport-wide 77.9%.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| ATL to LGA · New York | 8,502 | 72.3% | 79 min | 4.34% | C− |
| ATL to MCO · Orlando | 8,267 | 70.3% | 75 min | 1.58% | C |
| ATL to FLL · Fort Lauderdale | 7,371 | 70.7% | 66 min | 2.46% | C |
| ATL to DCA · Washington | 6,798 | 68.7% | 70 min | 3.43% | C− |
| ATL to DFW · Dallas-Fort Worth | 6,672 | 73.9% | 82 min | 2.50% | C |
| ATL to ORD · Chicago | 6,493 | 69.0% | 83 min | 2.40% | C |
| ATL to MIA · Miami | 6,280 | 71.2% | 73 min | 1.61% | C |
| ATL to EWR · Newark | 6,246 | 72.3% | 78 min | 3.78% | C− |
| ATL to TPA · Tampa | 6,204 | 73.0% | 64 min | 1.34% | C |
| ATL to PHL · Philadelphia | 5,793 | 74.6% | 81 min | 3.28% | C− |
| ATL to DEN · Denver | 5,594 | 78.0% | 61 min | 1.11% | B |
| ATL to BWI · Baltimore | 5,402 | 75.2% | 63 min | 2.26% | B |
| ATL to BOS · Boston | 5,054 | 72.8% | 66 min | 2.30% | C |
| ATL to IAH · Houston | 4,965 | 76.9% | 69 min | 1.79% | B |
| ATL to LAX · Los Angeles | 4,851 | 77.8% | 65 min | 0.82% | B+ |
| ATL to DTW · Detroit | 4,821 | 76.4% | 64 min | 0.81% | B+ |
| ATL to LAS · Las Vegas | 4,758 | 74.8% | 63 min | 0.78% | C+ |
| ATL to RDU · Raleigh | 4,642 | 80.0% | 62 min | 1.53% | B |
| ATL to AUS · Austin | 4,497 | 81.0% | 59 min | 1.27% | B |
| ATL to CLT · Charlotte | 4,381 | 80.1% | 74 min | 1.89% | B |
| ATL to BNA · Nashville | 4,258 | 79.6% | 59 min | 1.62% | B |
| ATL to JFK · New York | 4,218 | 74.6% | 81 min | 2.80% | C |
| ATL to JAX · Jacksonville | 4,076 | 75.1% | 56 min | 1.59% | B |
| ATL to IAD · Washington | 4,005 | 76.4% | 79 min | 2.12% | B |
| ATL to MSY · New Orleans | 4,002 | 81.4% | 59 min | 1.45% | B |
Departure window
The best time of day to leave ATL
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 19 points, against 16 points between the best and worst carrier.
- 5am–8am21,676 flights88.3%
- 8am–11am66,076 flights85.7%
- 11am–2pm50,625 flights82.2%
- 2pm–5pm60,852 flights74.5%
- 5pm–8pm50,195 flights69.2%
- 8pm–5am66,303 flights72.9%
Scale runs 60% to 95%.
Book the early departure. Flights leaving between 5am–8am arrive on time 88.3% of the time, against 69.2% for the evening window. That is 19 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 66,303 flights scheduled in it.
Explore
Filter ATL departures by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On departures from Atlanta (ATL), the best departure window is 5am–8am at 88.3% on time and the worst is 5pm–8pm at 69.2%, a wide gap of 19.1 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am88.3%
- 8–11am85.7%
- 11am–2pm82.2%
- 2–5pm74.5%
- 5–8pm69.2%
- 8pm–5am72.9%
best all US flightsScale 60% to 95%.
Across the year
When ATL runs late
ATL's year swings by 20 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 66.5% on time, 20 points below September, the best at 86.5%. 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. July was the busiest month here, with 28,068 flights.
Across the week, Wednesday is the strongest day at 84.2% on time and Sunday the weakest at 72.3%, a spread of 12 points.
ATL month by month
From Europe
Transatlantic routes into ATL
19 European airports send scheduled passenger flights to ATL, 19,364 flights a year in both directions by the DOT's international count. The DOT keeps no delay record for international flights; the UK routes carry the CAA's departure punctuality, and every route sets its departure airport's EUROCONTROL figures beside ATL's own record above.
- LHR to ATL · London3,607 flights
- CDG to ATL · Paris3,078 flights
- AMS to ATL · Amsterdam2,870 flights
- FRA to ATL · Frankfurt1,398 flights
- FCO to ATL · Rome1,355 flights
- BCN to ATL · Barcelona769 flights
- MUC to ATL · Munich679 flights
- MAD to ATL · Madrid672 flights
- ATH to ATL · Athens644 flights
- MXP to ATL · Milan642 flights
- MAN to ATL · Manchester628 flights
- DUB to ATL · Dublin576 flights
Delay causes
Why ATL gets delayed
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 4.52 million reported delay minutes.
- 42%Carrier
- 30%Late-arriving aircraft
- 22%National Airspace System
- 5%Extreme weather
- 0%Security
The largest share of delay minutes, 42%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1.89 million of the 4.52 million delay minutes reported here. The split is drawn from 4,517,157 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 88.3% on time here.
Cancellations sit at 1.83% against a national 1.89%, which is ordinary. Diversions add another 0.27%.
7.6% 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 about an hour, which a normal layover absorbs.
315,727 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.
What to do with this
Flying out of ATL
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 86.5% on time and July 66.5%, a swing of 20 points. If the dates move at all, move them out of July before you think about anything else. 309,101 completed flights over 12 months sit behind that.
Common questions
ATL delay questions
How often is Atlanta (ATL) delayed?
Roughly 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 22.1% of the 315,727 flights in this analysis, against 22.7% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on Atlanta (ATL)?
United Airlines leads at 79.7% on time across 7,672 flights. Frontier Airlines is at the other end on 63.7%, 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 Atlanta (ATL)?
The 5am–8am departure window is the strongest at 88.3% on time. The 5pm–8pm window is the weakest at 69.2%, 19 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 Atlanta (ATL)?
July is the weakest month at 66.5% on time, compared with 86.5% in September. Across the year that is 20 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
- ATL to LGA — New York72.3%
- ATL to MCO — Orlando70.3%
- ATL to FLL — Fort Lauderdale70.7%
- ATL to DCA — Washington68.7%
- ATL to DFW — Dallas-Fort Worth73.9%
- ATL to ORD — Chicago69.0%
- Delta Air Lines on-time record79.5%
- Frontier Airlines on-time record63.7%
- Southwest Airlines on-time record76.4%
- United Airlines on-time record79.7%
- The best time of day to fly, according to 7.05 million flight records
- US airports with the biggest gap between their best and worst month
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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.