Guide
The airports where departure time matters most
Nationally, 5am–8am departures beat 5pm–8pm by 21.3 points. At Dallas (DAL) the gap is 31.6 points; at Honolulu (HNL), 9.9. Here is where the first flight is worth paying for.
Flights scheduled to leave Dallas Love Field between 5am and 8am arrived on time 91.5% of the time over September 2025 to August 2026. Flights leaving the same airport between 5pm and 8pm, almost all of them on the same airline, managed 59.9%.
That is a 31.6-point swing between breakfast and dinner, against a national gap of 21.3 points.
Fly out of Daniel K. Inouye International instead and the same comparison shrinks to 9.9 points. The rule that the first flight of the day is the safest one holds at almost every one of the 60 airports with a page on this site. How much it is worth paying for is a different question at each of them.
Every airport figure here covers flights departing that airport, grouped by scheduled local departure time and scored at the gate at the other end. An evening departure from Love Field counts as late if it lands in Houston 20 minutes behind schedule, whatever caused it. (Scheduled, not actual: grouping by pushback time would hide the very delay being measured.)
The steep end
5am–8am5pm–8pm
50.0%100.0%
On-time percentages for departures scheduled 5am–8am and 5pm–8pm local time. Source: US DOT Bureau of Transportation Statistics, September 2025 to August 2026.
The morning numbers barely differ. What separates these airports is how far the evening falls, and at the top it falls a long way: 59.9% at Love Field, 59.6% at Fort Lauderdale, 62.0% at Orlando.
Florida: the afternoon storm and the full schedule
Six Florida airports sit in or near the top of the ranking, and the most familiar explanation is correct as far as it goes. From late spring into early autumn, sea-breeze convergence builds thunderstorms over the peninsula most afternoons, peaking between roughly 3pm and 8pm, exactly when the evening departures push back. A line of storms reroutes every northbound departure, and aircraft that should have turned in 45 minutes sit on the ramp.
The calendar complicates the picture. Fort Lauderdale's worst month was March at 59.7% on time, Palm Beach's March, Fort Myers's March. That is peak leisure season, not storm season, when schedules are at their densest and aircraft arrive from a northern network that has had its own day. Evening departures in Florida inherit both problems: afternoon weather in summer, and in winter a queue of inbound aircraft that left Boston, New York and Chicago late.
Either way, the morning is insulated. Dawn departures from Palm Beach International ran 93.7% on time, among the best first-wave figures in the country.
Love Field: one airline, one rotation
Dallas Love Field is a Southwest airport in a way few others are. Almost every departure is a Southwest flight, and Southwest does not run hub banks. Its aircraft fly point to point, several legs a day, with turns scheduled as tight as the operation allows.
That model is fragile in one specific way. A 30-minute delay on the 7am leg does not stay on the 7am leg. It rides the same airframe to Houston, to Nashville, to Denver and back, and every turn is a chance to add to it but rarely a chance to recover it. The DOT's cause codes show the result. At Love Field, late-arriving aircraft account for 50% of delay minutes, against 40% nationally, and the air traffic system only 16%. I read those two numbers together as the whole story of Love Field's evening.
The problem is not the sky. It is the plane that arrives from somewhere else already behind.
The same airline's other big city bases point the same way: William P. Hobby spreads 26.3 points and Chicago Midway International 26.0. Across its whole network Southwest's early-morning departures beat its evening ones by 30.7 points, among the widest gaps of the 14 carriers.
US average 21.3 pts
0.0 pts35.0 pts
Points between 5am–8am and 5pm–8pm departures across each airline's whole network. Source: US DOT Bureau of Transportation Statistics, September 2025 to August 2026.
The airline alone does not explain Love Field, though. Southwest also dominates several California airports, and their curves are flatter. Rotations propagate delay; Texas summer weather supplies the delay to propagate. Love Field's worst month was June, at 56.5% on time, and its late-night departures after 8pm ran just 53.5%.
Washington National: capacity with no slack
Ronald Reagan Washington National spreads 29.6 points, one of the steepest curves outside Florida and Texas. National is one of the few US airports where the FAA caps hourly operations through slots, and its main runway is short by hub standards, so the schedule sits close to what the field can physically handle all day. There is no spare capacity to absorb a bad hour. Late-arriving aircraft account for 49% of its delay minutes, and many evening departures head up the Northeast corridor into New York's and Boston's own evening peaks. At 60.1% on time, I would not put a tight connection behind an evening flight out of National.
The flat end
5am–8am5pm–8pm
65.0%100.0%
On-time percentages for departures scheduled 5am–8am and 5pm–8pm local time. Source: US DOT Bureau of Transportation Statistics, September 2025 to August 2026.
Flat has two causes. The first is an airport that is simply good all day. Salt Lake City International is among the most punctual airports in the data at 84.2%, and its evening departures ran 79.4% on time, against 77.3% for all US flights at any hour. Its curve is flat because it never gets bad. Portland International has a similar profile: 77.5% in the evening, with a first wave (88.1%) that is about level with the national first wave rather than ahead of it.
The second is an airport whose curve has a different shape. At Daniel K. Inouye International the worst window is 2pm–5pm, Kahului Airport follows the same pattern, and at both the evening recovers. Inter-island flying runs short sectors within a closed network, far from any mainland congestion, and the air traffic system accounts for just 11% of Honolulu's delay minutes.
Los Angeles shows a West Coast version of the same thing. Its dawn departures are its best, at 90.1%, but its worst window was 11am–2pm at 76.0%, and its evening departures (76.4%) did slightly better than that. By 6pm in Los Angeles it is 9pm in the East and the eastern arrival peaks have cleared, so an evening flight east is likely landing into quieter airspace than a mid-afternoon one. San Francisco has a sharper version: its curve drops hard after the first wave, which is consistent with the morning low-cloud arrival programmes that hold aircraft inbound to SFO and leave the late-morning departures waiting for them.
Dallas (DAL)72.6% overall
Fort Lauderdale (FLL)70.4% overall
Washington (DCA)72.2% overall
San Francisco (SFO)75.3% overall
Los Angeles (LAX)79.5% overall
Salt Lake City (SLC)84.2% overall
All panels share one scale. Windows run 5am, 8am, 11am, 2pm, 5pm and 8pm to 5am. Source: US DOT Bureau of Transportation Statistics, September 2025 to August 2026.
Dulles is the other exception worth knowing. Its dawn departures run 85.8% on time, and its best window is 8am–11am at 88.8%. At Dulles, a 9am departure gives up little or nothing to a 6am.
How I pick a departure time
One year of data is one summer and one winter, and a single bad July can move an airport's evening figure several points. Read the ranking as a shape rather than a league table: the airports near the top are there for structural reasons that do not change year to year.
At a steep airport, pay for the first wave. From Love Field, Florida or Washington National, a dawn departure is worth an earlier alarm and a less convenient connection. If it were my ticket out of Love Field, nothing after 5pm would carry an onward connection. The difference between 89.8% and 59.6% at Fort Lauderdale is the difference between a late flight being unusual and it being routine.
In summer in Florida and Texas, move the connection too. An 11am departure still runs ahead of the evening at these airports, but the afternoon storm window is where the curve falls fastest. Connect before 2pm when you can.
At a flat airport, book on price and convenience. From Salt Lake City, Portland or Honolulu the evening flight gives up far less, and a cheaper 6pm departure is usually a fair trade. In Los Angeles, a mid-afternoon departure is the one to avoid, not the evening one.
Check your own airport before assuming the national rule. Every airport page shows its own six-window breakdown, and the best time to fly tool runs the same comparison for a specific route. The national gap of 21.3 points is an average of airport curves that run from 9.9 points to 31.6.
Check the curve at your airport: Dallas Love Field (DAL) · Fort Lauderdale (FLL) · Washington National (DCA) · Salt Lake City (SLC) · Los Angeles (LAX) · Best time to fly tool