Route profile
LAS→IAD
Flight reliability, delays and best times to fly from Las Vegas to Washington, 2,065 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 84% of comparable major US routes (4,598 compared)
Calculated from 3,176 flights. How this is calculated · What counts as on time
LAS → IAD arrives on time 84.6% of the time; the return trip, IAD → LAS, arrives on time 83.0% of the time.
LAS → IAD spends 26.4 minutes on the ground on a 2,065-mile trip: 18.7 minutes from pushback to wheels-up at LAS and 7.7 minutes from touchdown to gate at IAD.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
Unlike most, it barely matters what time you fly this route, a steadier spread than 90% of 4,023 comparable routes.
89.6% on time for 5–9 AM departures, against 80.5% for 12–3 PM, a narrow gap either way.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,023 in the comparison.
What sets this route apart
Where LAS to IAD differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
LAS to IAD is at its best against routes of similar length for flights scheduled at 11 PM: 86.3% arrive on time, 5.5 points ahead of the 80.8% those routes manage at that hour. Against all other routes the gap is 7.2 points.
LAS to IAD holds up on Wednesdays better than routes of similar length do: 89.6% on time to their 81.3%, a 8.3 points lead. Against all other routes the gap is 8.8 points.
April is kinder to LAS to IAD than to routes of similar length: 90.7% on time against 81.1%, 9.6 points better. Against all other routes the gap is 10.8 points.
United Airlines does better on LAS to IAD than on its routes of similar length: 85.6% on time here, 81.7% there, 3.9 points apart. Against all other routes the gap is 5.7 points.
LAS to IAD against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 11 PM departures | 86.3% | routes of similar length | 80.8% | +5.5 pts | 839 here, 57,088 there |
| Weekday: Wednesday | 89.6% | routes of similar length | 81.3% | +8.3 pts | 443 here, 129,771 there |
| Month: April | 90.7% | routes of similar length | 81.1% | +9.6 pts | 289 here, 77,178 there |
| Airline: United Airlines | 85.6% | routes of similar length | 81.7% | +3.9 pts | 2,948 here, 155,998 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 2,065 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
When it goes wrong
July 2023 – July 2026
29 min late
against a median of 10 min early
Percentiles over 3,176 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at IAD after arriving from LAS.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 29% | High risk |
| 45 min | 15% | Some risk |
| 60 min | 9.5% | Some risk |
| 90 min | 5.1% | Some risk |
| 120 min | 3.4% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.91% of the time and diverts 0.44% of the time, which a late arrival never shows up in.
Chance of missing is the share of 3,133 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 29 minutes late (90th-percentile gate arrival delay), over 3,176 operations.
Any other layover length: connection checker.
Best time to fly
LAS → IAD flights departing 5–9 AM arrived on time 89.6% of the time, against 80.5% for 12–3 PM departures, a gap of 9.1 percentage points.
By departure window
By departure hour
- 12 AM to 7 AM: too few flights to score
- 8 AM: 89.2% on time from 926 flights
- 9 AM to 12 PM: too few flights to score
- 1 PM: 80.4% on time from 1,059 flights
- 2 PM to 10 PM: too few flights to score
- 11 PM: 86.3% on time from 848 flights
Departure windows with fewer than 120 flights are not scored.
Why LAS → IAD runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
Share of the delay minutes US DOT attributed to each cause for LAS → IAD. Only delays of 15 minutes or more are attributed. What the five causes mean
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 2,991 | 85.6% | 0.97% | -11 min | 4.9% |
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Sunday the least, a gap of 9.4 percentage points.
By month
- Jan: 89.5%
- Feb: 87.8%
- Mar: 83.1%
- Apr: 90.7%
- May: 82.1%
- Jun: 76.7%
- Jul: 70.6%
- Aug: 83.8%
- Sep: 89.9%
- Oct: 93.1%
- Nov: 86.9%
- Dec: 86.0%
July is historically the weakest month and October the strongest, a spread of 22.5 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: too few flights to score (59)
- August 2023: too few flights to score (62)
- September 2023: too few flights to score (60)
- October 2023: too few flights to score (62)
- November 2023: too few flights to score (61)
- December 2023: too few flights to score (63)
- January 2024: too few flights to score (75)
- February 2024: too few flights to score (83)
- March 2024: too few flights to score (90)
- April 2024: too few flights to score (90)
- May 2024: too few flights to score (84)
- June 2024: too few flights to score (61)
- July 2024: too few flights to score (61)
- August 2024: too few flights to score (57)
- September 2024: too few flights to score (80)
- October 2024: too few flights to score (93)
- November 2024: too few flights to score (89)
- December 2024: too few flights to score (81)
- January 2025: too few flights to score (89)
- February 2025: too few flights to score (100)
- March 2025: too few flights to score (99)
- April 2025: 90.0% from 120 flights
- May 2025: 79.2% from 145 flights
- June 2025: too few flights to score (111)
- July 2025: 77.9% from 123 flights
- August 2025: too few flights to score (119)
- September 2025: too few flights to score (90)
- October 2025: too few flights to score (93)
- November 2025: too few flights to score (89)
- December 2025: too few flights to score (92)
- January 2026: too few flights to score (91)
- February 2026: too few flights to score (74)
- March 2026: too few flights to score (81)
- April 2026: too few flights to score (81)
- May 2026: too few flights to score (86)
- June 2026: too few flights to score (90)
- July 2026: too few flights to score (92)
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 86.2% against 85.0% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 3,176 LAS → IAD flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed