Carrier route record
WNDAL→ATL
Southwest Airlines · Dallas to Atlanta
- Flights
- 1,547
- Period
- July 2025 to June 2026
- Share of route
- 46%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on DAL to ATL sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 1,547 flights, with a median arrival 3 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate Southwest on DAL to ATL from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
75.6%
Arrivals under 15 minutes late, of 1,517 completed flights
Avg delay
60 min
Across delayed arrivals only, not all flights
Cancelled
1.75%
National rate is 1.81%
Whole route
79.2%
Every carrier on DAL to ATL, 3,398 flights
These figures cover 1,547 flights between July 2025 and June 2026. Beyond the headline rate, 8.0% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Southwest against every carrier on DAL to ATL
Southwest flew 1,547 of the 3,398 flights on DAL to ATL, about 46% of it. Its 75.6% on time is 4 points worse than the route as a whole, which runs 79.2%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from Delta at 82.1% to Southwest at 75.6%.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 1,851 | 82.1% | 90 min | 2.11% | B |
| Southwest Airlines (this page) | 1,547 | 75.6% | 60 min | 1.75% | B |
Departure window
When Southwest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 39 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am178 flights92.7%
- 8am–11am390 flights88.4%
- 11am–2pm255 flights80.4%
- 2pm–5pm348 flights71.5%
- 5pm–8pm285 flights53.5%
- 8pm–5am91 flights59.6%
Scale runs 45% to 100%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 53.5% on time, against 92.7% 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 8am–11am window is the busiest, with 390 flights scheduled in it.
Across the year
Southwest on DAL to ATL through the year
June is the worst month at 58.3% on time, 29 points below September, the best at 87.3%. 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. October was the busiest month here, with 146 flights.
Across the week, Tuesday is the strongest day at 83.1% on time and Sunday the weakest at 71.6%. 12 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Southwest runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 55% of the 22,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 55%Late-arriving aircraft
- 28%Carrier
- 14%National Airspace System
- 3%Extreme weather
- 0%Security
55% 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 22,000 reported delay minutes here, that single category outweighs weather by 19 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 22,026 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 92.7% on time here.
Cancellations sit at 1.75% against a national 1.81%, which is ordinary. Diversions add another 0.19%.
Connections and stage length
What a delay here costs
8.0% 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 last about an hour, which a normal layover absorbs.
The 721 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg runs 77.6% on time across 1,548 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 1,547 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.
What to do with this
Booking Southwest on DAL to ATL
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 87.3% on time and June 58.3%, a swing of 29 points. If the dates move at all, move them out of June before you think about anything else. 1,517 completed flights over 12 months sit behind that.
Related
Where to go next
- DAL to ATL, every carrier
- Southwest on ATL to DAL, the return leg
- Delta Air Lines on DAL to ATL82.1%
- Southwest Airlines network-wide record
- Dallas Love Field (DAL) delay statistics
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.