IAD to PHX flight delays
Washington, VA (IAD) Phoenix, AZ (PHX) · 1,956 miles
2,340 flights · July 2024 – July 2026 · US Bureau of Transportation Statistics
81.24%
Arrived on time
Within 15 minutes of schedule
0.68%
Cancelled
Share of scheduled flights
65 min
When late, late by
Average across delayed arrivals
13 min
Delay per flight
Averaged over every flight flown
What the record says about this route
Which airline you fly changes the odds here. United Airlines arrived on time 13.4 points more often than Southwest Airlines over the same period on the same route — same airports, same weather, same air traffic control. A gap that survives all of that is about how the two airlines are run.
The season swings this route hard. In October it ran 36 points more punctual than in July — a difference bigger than the one between the best and worst airlines on most routes. If the date is flexible, it is worth more than the carrier.
The Washington to Phoenix route sits close to the middle of the record — neither notably punctual nor notably late.
Which airline should you fly on this route?
Over July 2024 – July 2026, United Airlines arrived on time most often on IAD to PHX. Southwest Airlines was late most often. Flights ran closest to schedule in March and worst in July.
Every airline on IAD to PHX
Ranked by how many flights each one operated. A carrier with fewer than 100 flights in the period is listed but not graded.
| Airline | Flights | On time | Cancelled | Avg delay | Grade |
|---|---|---|---|---|---|
| United Airlines | 1,640 | 85.24% | 0.73% | 76 min | B |
| Southwest Airlines | 700 | 71.86% | 0.57% | 53 min | D |
Month by month
Share of flights that arrived within 15 minutes of schedule, by month flown.
The return leg
PHX to IAD Phoenix back to Washington 85.36% on time BOther routes from Washington
Common questions
Are flights from Washington to Phoenix usually delayed?
81.24% of flights on the IAD to PHX route arrived within 15 minutes of schedule, so roughly 2 in every ten arrived late. That is better than the average route in this record.
Which airline is most on time from Washington to Phoenix?
United Airlines, at 85.24% on time across 1,640 flights. The least punctual on the route was Southwest Airlines at 71.86%.
How often are IAD to PHX flights cancelled?
0.68% of scheduled flights did not operate — about 7 in every thousand. That is in the normal range.
What is the best month to fly Washington to Phoenix?
October, when 94.9% of flights arrived on time. The worst was July at 58.9%.
When IAD to PHX flights are late, how late are they?
About 65 minutes on average across the flights that arrived more than 15 minutes behind schedule.
What these figures do and do not tell you
Everything on this page is counted from the flights that actually operated on IAD to PHX during July 2024 – July 2026, as reported by the airlines to the US Bureau of Transportation Statistics. "On time" is the federal definition: arriving at the gate within 15 minutes of the scheduled time.
A route's record is a description of the past, not a forecast. Weather, air traffic control and the aircraft's earlier flights that day drive most delays, and none of them are predictable from a historical rate. What the record does tell you is whether this route runs late more often than others, and which carrier on it has the better history — which is the part you can actually act on when you book.
Cancellations are counted separately from delays because they are a different problem for a traveller: a late flight still gets you there. How the grade is calculated →