FlightRecord

Washington (IAD) to Phoenix (PHX): On-Time Performance

Data through May 2026

When you fly IAD to PHX matters as much as anything else about the booking: the route swung from 95% on-time in October 2024 to just 59% in July 2025. Across the full period the route averages 81% on-time against a national 78%. Morning departures also hold up better than evening ones (93% vs 73%), which matters most in the rough months.

On-time
81%
arrived <15 min late
Avg delay
13 min
completed flights
Cancelled
0.7%
Flights/day
3.2
last 12 months
Duration
5h 2m
scheduled
Distance
1,956 mi

Best airline from IAD to PHX

2 airlines flew this route regularly between 2024-06 and 2026-05.

AirlineOn-timeAvg delayCancelledFlights
United Airlinesmost reliable85%12 min0.7%1,670
Southwest Airlines71%17 min0.6%727

Monthly on-time trend

Monthly on-time percentage for IAD to PHX flights50%75%100%June 2024: 68% on-time (90 flights)68Jun 2024July 2024: 64% on-time (93 flights)64August 2024: 78% on-time (93 flights)78September 2024: 87% on-time (90 flights)87Sep 2024October 2024: 95% on-time (98 flights)95November 2024: 89% on-time (117 flights)89December 2024: 88% on-time (124 flights)88Dec 2024January 2025: 74% on-time (87 flights)74February 2025: 86% on-time (94 flights)86March 2025: 90% on-time (124 flights)90Mar 2025April 2025: 79% on-time (120 flights)79May 2025: 79% on-time (113 flights)79June 2025: 72% on-time (90 flights)72Jun 2025July 2025: 59% on-time (92 flights)59August 2025: 83% on-time (88 flights)83September 2025: 75% on-time (87 flights)75Sep 2025October 2025: 75% on-time (97 flights)75November 2025: 75% on-time (109 flights)75December 2025: 82% on-time (108 flights)82Dec 2025January 2026: 89% on-time (98 flights)89February 2026: 84% on-time (81 flights)84March 2026: 84% on-time (117 flights)84Mar 2026April 2026: 89% on-time (91 flights)89May 2026: 84% on-time (96 flights)84

Best time to fly from IAD to PHX

Aim for departures around 8 a.m. (93% on-time); avoid 6 p.m. departures (63%).

On-time percentage by scheduled departure hour, IAD to PHX8 a.m.: 93% on-time (542 flights)812 p.m.: 88% on-time (369 flights)121 p.m.: 81% on-time (31 flights)132 p.m.: 83% on-time (23 flights)143 p.m.: 83% on-time (137 flights)154 p.m.: 74% on-time (220 flights)165 p.m.: 73% on-time (934 flights)176 p.m.: 63% on-time (73 flights)187 p.m.: 75% on-time (44 flights)19scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday80%12 min
Tuesdaybest84%12 min
Wednesday79%14 min
Thursday78%11 min
Friday79%15 min
Saturday83%14 min
Sunday82%15 min

What causes delays on this route

Share of total delay minutes by cause, as reported by carriers to the US DOT.

  • Late-arriving aircraft39%
  • Airline operations30%
  • National airspace system27%
  • Weather5%

Frequently asked questions

How often are flights from IAD to PHX delayed?
19% of IAD–PHX flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 13 minutes.
Which airline is most reliable from IAD to PHX?
United Airlines has the best on-time record on this route at 85%, based on 1,670 flights. 2 airlines flew IAD–PHX frequently enough to compare in this period.
What is the best time of day to fly from IAD to PHX?
Departures around 8 a.m. have the best record (93% on-time), while departures around 6 p.m. have the worst (63%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from IAD to PHX?
The scheduled IAD–PHX flight time averages 5h 2m over 1,956 miles. Actual arrival times vary — flights on this route land 15+ minutes late 19% of the time.
How often are IAD to PHX flights cancelled?
0.7% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
What is the worst month to fly from IAD to PHX?
July 2025 was the roughest month in this dataset, with only 59% of arrivals on time. The best was October 2024 at 95%. If your dates are flexible, that 36-point gap is worth planning around.

Based on 2,397 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.