Best Time to Fly IAD to PIT: On-Time Stats by Hour & Airline
Washington Dulles International → Pittsburgh International
Data through July 2026 · Last updated October 18, 2026
1,227 flights were scheduled from Washington (IAD) to Pittsburgh (PIT) in the last 12 months, and 84.8% of those that flew arrived on time, 7.2 points above the US average of 77.6%.
United Airlines was the most punctual of the 2 airlines on the route at 87.1%, while Republic Airways trailed at 83.2%.
April has been the best month (92% on time) and Sunday the weakest day of the week (78%).
1.6% of flights were cancelled, versus 1.8% nationally.
IAD to PIT 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 | 87.1% | 77 min | 0.8% | 516 |
| Republic Airways | 83.2% | 69 min | 2.1% | 711 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly IAD to PIT
On-time arrival % by scheduled departure hour (local time), 2,169 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 8am–9am | 92.9% | 1.0% | 300 |
| 12pm–1pm | 87.9% | 1.1% | 528 |
| 1pm–2pm | 90.7% | 0.0% | 43 |
| 3pm–4pm | 75.7% | 0.9% | 108 |
| 5pm–6pm | 78.1% | 2.4% | 544 |
| 10pm–11pm | 80.0% | 2.3% | 646 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on IAD to PIT
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) | 90.9% | +5.2 pts | 0.0% | 44 |
| Christmas & New Year (Dec 20 - Jan 3) | 71.4% | -14.3 pts | 0.0% | 70 |
| Summer peak (Jun 15 - Aug 15) | 73.5% | -12.2 pts | 5.0% | 377 |
| All other days | 85.7% | — | 1.1% | 1,678 |
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).