Best Time to Fly LAX to IAD: On-Time Stats by Hour & Airline
Los Angeles International → Washington Dulles International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 87.5% of Los Angeles (LAX) to Washington (IAD) flights arrived on time (2,474 scheduled flights). That is 9.9 points above the national average of 77.6%.
United Airlines was the most punctual of the 2 airlines on the route at 88.0%, while American Airlines trailed at 76.5%.
April has been the best month (93% on time) and Saturday the weakest day of the week (83%).
0.6% of flights were cancelled, versus 1.8% nationally.
LAX to IAD on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| United Airlines | 88.0% | 53 min | 0.6% | 2,339 |
| American Airlines | 76.5% | 70 min | 0.0% | 116 |
| Alaska Airlines | Limited data | 19 | ||
80%+ good 70–79.9% fair <70% poor
Best time of day to fly LAX to IAD
On-time arrival % by scheduled departure hour (local time), 5,078 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 12am–1am | Limited data | 18 | |
| 6am–7am | 96.3% | 1.1% | 191 |
| 8am–9am | 79.2% | 0.9% | 996 |
| 9am–10am | 95.7% | 0.0% | 94 |
| 10am–11am | 88.1% | 0.2% | 604 |
| 11am–12pm | 89.1% | 0.0% | 92 |
| 12pm–1pm | 85.0% | 0.3% | 310 |
| 1pm–2pm | 86.4% | 0.4% | 496 |
| 4pm–5pm | 91.5% | 0.2% | 458 |
| 5pm–6pm | 65.1% | 0.0% | 43 |
| 8pm–9pm | 87.9% | 0.0% | 33 |
| 9pm–10pm | 90.3% | 0.5% | 593 |
| 10pm–11pm | 86.4% | 0.7% | 414 |
| 11pm–12am | 88.0% | 0.7% | 736 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on LAX to IAD
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 91.6% | +3.2 pts | 1.0% | 96 |
| Christmas & New Year (Dec 20 - Jan 3) | 80.8% | -7.5 pts | 0.5% | 221 |
| Summer peak (Jun 15 - Aug 15) | 80.9% | -7.5 pts | 0.5% | 948 |
| All other days | 88.3% | — | 0.5% | 3,813 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).