Best Time to Fly PDX to IAD: On-Time Stats by Hour & Airline
Portland International → Washington Dulles International
Data through July 2026 · Last updated October 18, 2026
291 flights were scheduled from Portland (PDX) to Washington (IAD) in the last 12 months, and 93.4% of those that flew arrived on time, 15.8 points above the US average of 77.6%.
United Airlines was the only reporting airline with regular flights on this route.
Over 24 months, Tuesday was the most reliable day (95% on time) and July the worst month (70%).
The cancellation rate was 0.7% (US average 1.8%).
PDX 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 | 93.4% | 81 min | 0.7% | 291 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly PDX to IAD
On-time arrival % by scheduled departure hour (local time), 582 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 6am–7am | Limited data | 20 | |
| 7am–8am | Limited data | 17 | |
| 8am–9am | 95.3% | 0.0% | 319 |
| 10pm–11pm | Limited data | 21 | |
| 11pm–12am | 82.5% | 1.9% | 205 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on PDX 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) | Limited data | 14 | ||
| Christmas & New Year (Dec 20 - Jan 3) | 100.0% | +6.3 pts | 0.0% | 30 |
| Summer peak (Jun 15 - Aug 15) | 76.9% | -16.8 pts | 1.6% | 124 |
| All other days | 93.7% | — | 0.5% | 414 |
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).