ON TIMEBOARD

LAX → IAD on time

Los Angeles LAX (Los Angeles, CA) to Washington Dulles (Washington, DC). Every scheduled flight, September 2025 to August 2026.

On time
87%
arrived < 15 min late
Cancelled
0.5%
2,461 flights
Typical arrival
−11 min
median vs schedule
When late
+56 min
average delay
Flights / day
7
2 airlines

87% of flights from Los Angeles to Washington arrived on time over the past 12 months. That is better than the typical U.S. route. The 10 p.m. departures ran on time 90% of the time; the 8 a.m. ones 80%. Most reliable airline: United Airlines (87%). 4% of flights arrived more than an hour late or not at all.

How late?

The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for LAX → IAD: when a flight was late, it was under 45 minutes late 62% of the time. About 1 in 31 flights landed an hour or more late, and 1 in 205 three hours or more; 0.5% were cancelled outright.

Share of all 2,461 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
United Airlines2,34187%0.6%−11 min3.0%+54 minUnited Airlines
American Airlines12076%0.0%−4 min7.5%+71 minAmerican Airlines

Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.

Best time of day to fly

On-time rate by scheduled departure hour (local time at LAX). Delays build through the day as late planes knock on, so early flights usually do best.

40%70%100%6 a.m. departures: too few flights (74 flights)6a7 a.m. departures: too few flights7a8 a.m. departures: 80% on time (366 flights)808a9 a.m. departures: too few flights9a10 a.m. departures: 89% on time (321 flights)8910a11 a.m. departures: too few flights (63 flights)11anoon departures: 86% on time (238 flights)8612p1 p.m. departures: 86% on time (198 flights)861p2 p.m. departures: too few flights2p3 p.m. departures: too few flights3p4 p.m. departures: 90% on time (262 flights)904p5 p.m. departures: too few flights5p6 p.m. departures: too few flights6p7 p.m. departures: too few flights7p8 p.m. departures: too few flights (12 flights)8p9 p.m. departures: 87% on time (332 flights)879p10 p.m. departures: 90% on time (235 flights)9010p11 p.m. departures: 86% on time (360 flights)8611p
LAX → IAD, share of flights arriving on time, by departure hour. Hours with under 100 flights are greyed out.
82%+ on time76–82%68–76%under 68%too few flights

By airline and hour

DepartsUnited AirlinesAmerican Airlines
8 a.m.79%—
10 a.m.89%—
noon86%—
1 p.m.86%—
4 p.m.90%—
9 p.m.93%76%
10 p.m.90%—
11 p.m.86%—

Last flight of the day

On LAX → IAD, each airline's last flight of the day was cancelled 0.8% of the time, against 0.5% for its earlier flights (1.6× as often). It arrived 3+ hours late 0.0% of the time (earlier flights: 0.6%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.

AirlineLast departureLast: cancelledLast: 3h+ lateEarlier: cancelledNext morning
United Airlines11:30 p.m.0.8%0.0%0.5%first flight 6:00 a.m.

Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.

If you need to be in IAD tonight, book an earlier flight so there's a backup if it's cancelled.

By month

Each calendar month pooled over 2023–2026. Best: April (93%). Worst: July (75%).

40%70%100%Jan: 77% on time (481 flights)77JanFeb: 85% on time (450 flights)85FebMar: 80% on time (604 flights)80MarApr: 93% on time (698 flights)93AprMay: 89% on time (749 flights)89MayJun: 86% on time (717 flights)86JunJul: 75% on time (710 flights)75JulAug: 84% on time (618 flights)84AugSep: 89% on time (586 flights)89SepOct: 91% on time (656 flights)91OctNov: 89% on time (620 flights)89NovDec: 78% on time (633 flights)78Dec

By day of week

DayFlightsOn timeCancelled
Monday36886%0.3%
Tuesday33090%0.0%
Wednesday33388%0.3%
Thursday37087%0.0%
Friday36187%1.1%
Saturday32683%0.3%
Sunday37386%1.6%

Why flights were late

Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.

Airline (crew, maintenance, ops) 42%Late inbound plane 40%Air traffic & airport (NAS) 18%

Cancellations: weather 7 · airline 6

Month by month

60%80%100%Sep 2023Jan 2024Jan 2025Jan 2026Sep 2023: 84% on time, 0.5% cancelledOct 2023: 89% on time, 0.0% cancelledNov 2023: 91% on time, 0.0% cancelledDec 2023: 69% on time, 0.0% cancelledJan 2024: 68% on time, 8.2% cancelledFeb 2024: 81% on time, 0.7% cancelledMar 2024: 78% on time, 0.0% cancelledApr 2024: 92% on time, 0.0% cancelledMay 2024: 89% on time, 0.0% cancelledJun 2024: 86% on time, 1.3% cancelledJul 2024: 77% on time, 2.0% cancelledAug 2024: 81% on time, 1.3% cancelledSep 2024: 93% on time, 0.0% cancelledOct 2024: 90% on time, 0.0% cancelledNov 2024: 91% on time, 0.4% cancelledDec 2024: 78% on time, 0.9% cancelledJan 2025: 83% on time, 1.9% cancelledFeb 2025: 87% on time, 0.7% cancelledMar 2025: 88% on time, 0.0% cancelledApr 2025: 92% on time, 0.0% cancelledMay 2025: 87% on time, 0.0% cancelledJun 2025: 81% on time, 0.0% cancelledJul 2025: 69% on time, 1.4% cancelledAug 2025: 86% on time, 0.5% cancelledSep 2025: 91% on time, 0.6% cancelledOct 2025: 95% on time, 1.0% cancelledNov 2025: 84% on time, 0.0% cancelledDec 2025: 86% on time, 0.5% cancelledJan 2026: 79% on time, 4.0% cancelledFeb 2026: 88% on time, 0.0% cancelledMar 2026: 75% on time, 0.0% cancelledApr 2026: 94% on time, 0.0% cancelledMay 2026: 90% on time, 0.0% cancelledJun 2026: 90% on time, 0.8% cancelledJul 2026: 81% on time, 0.0% cancelledAug 2026: 85% on time, 0.0% cancelled
Share of flights on time, by month (hover a point for cancellations)
LAX → IAD, monthly on-time and cancellation rate.

Flight numbers on this route

Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.

FlightDepartsFlightsOn timeCancelledTypical arrivalOperated by
UA 22688:15 a.m.20183%0.0%−6 minUnited Airlines
UA 266710:39 a.m.36590%0.3%−11 minUnited Airlines
UA 163512:43 p.m.34787%0.6%−11 minUnited Airlines
UA 15734:49 p.m.21291%0.0%−16 minUnited Airlines
UA 26329:30 p.m.19493%1.0%−18 minUnited Airlines
UA 228210:35 p.m.27788%0.4%−12 minUnited Airlines
UA 41811:20 p.m.14090%0.7%−14 minUnited Airlines

Worst days in the past year

DateFlightsOn timeCancelled
Jan 25, 202660%6
Jul 18, 2026714%0
Mar 13, 2026617%0
Mar 7, 2026520%0
Jan 10, 2026425%0

Nearby airport alternatives

Other ways to make the same trip, using airports within 60 miles of Los Angeles or Washington. None has been clearly more reliable than LAX → IAD.

RouteFlightsOn timeCancelled
LAX → IAD (this route)2,46187%0.5%
LAX → BWI Los Angeles LAX to Baltimore/Washington1,64780%0.8%
LAX → DCA Los Angeles LAX to Washington Reagan National1,45478%1.3%

Questions

How often are flights from LAX to IAD on time?

87% of 2,461 scheduled flights from Los Angeles, CA to Washington, DC arrived within 15 minutes of schedule between September 2025 and August 2026. 0.5% were cancelled.

What is the best time of day to fly LAX to IAD?

Flights scheduled to leave at 10 p.m. were the most reliable (90% on time). The 8 a.m. departures were the least (80%).

Which airline is most on time from LAX to IAD?

United Airlines: 87% of its 2,341 flights on the route arrived on time. American Airlines: 76%.

What month has the most delays from LAX to IAD?

July (75% on time). The best month is April (93%), over 2023–2026.

Is the last flight of the day from LAX to IAD more likely to be cancelled?

Yes. Each airline's last LAX–IAD flight of the day was cancelled 0.8% of the time over the past year, against 0.5% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.

Related

Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.