Las Vegas (LAS) to Washington (IAD): On-Time Performance
Data through July 2026
When you fly LAS to IAD matters as much as anything else about the booking: the route swung from 95% on-time in October 2025 to just 62% in July 2026. Across the full period the route averages 85% on-time against a national 78%.
- On-time
- 85%
- arrived <15 min late
- Avg delay
- 11 min
- completed flights
- Cancelled
- 0.6%
- Flights/day
- 3.0
- last 12 months
- Duration
- 4h 32m
- scheduled
- Distance
- 2,065 mi
Best airline from LAS to IAD
2 airlines flew this route regularly between 2024-07 and 2026-07.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlinesmost reliable | 86% | 10 min | 0.6% | 2,141 |
| Frontier Airlines | 68% | 20 min | 0.0% | 185 |
Monthly on-time trend
Best time to fly from LAS to IAD
Aim for departures around 7 a.m. (95% on-time); avoid 12 a.m. departures (61%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 84% | 14 min |
| Tuesdaybest | 90% | 5 min |
| Wednesday | 89% | 7 min |
| Thursday | 82% | 12 min |
| Friday | 83% | 10 min |
| Saturday | 85% | 9 min |
| Sunday | 79% | 19 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft37%
- Airline operations42%
- National airspace system21%
Frequently asked questions
- How often are flights from LAS to IAD delayed?
- 15% of LAS–IAD flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-07 and 2026-07. The average arrival delay across completed flights was 11 minutes.
- Which airline is most reliable from LAS to IAD?
- United Airlines has the best on-time record on this route at 86%, based on 2,141 flights. 2 airlines flew LAS–IAD frequently enough to compare in this period.
- What is the best time of day to fly from LAS to IAD?
- Departures around 7 a.m. have the best record (95% on-time), while departures around 12 a.m. have the worst (61%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from LAS to IAD?
- The scheduled LAS–IAD flight time averages 4h 32m over 2,065 miles. Actual arrival times vary — flights on this route land 15+ minutes late 15% of the time.
- How often are LAS to IAD flights cancelled?
- 0.6% of scheduled flights on this route were cancelled between 2024-07 and 2026-07, at or below the national rate of 1.6%.
- What is the worst month to fly from LAS to IAD?
- July 2026 was the roughest month in this dataset, with only 62% of arrivals on time. The best was October 2025 at 95%. If your dates are flexible, that 33-point gap is worth planning around.
Explore related pages
More routes from LAS
Other ways to fly to Washington (IAD)
Related guides
Based on 2,326 flights, 2024-07–2026-07. Source: US DOT Bureau of Transportation Statistics. Updated 2026-09-28.