Best Time to Fly PIT to IAD: On-Time Stats by Hour & Airline
Pittsburgh International → Washington Dulles International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 88.5% of Pittsburgh (PIT) to Washington (IAD) flights arrived on time (1,225 scheduled flights). That is 10.9 points above the national average of 77.6%.
Republic Airways was the most punctual of the 2 airlines on the route at 89.4%, while United Airlines trailed at 87.3%.
September has been the best month (93% on time) and Sunday the weakest day of the week (85%).
1.3% of flights were cancelled, versus 1.8% nationally.
PIT 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 |
|---|---|---|---|---|
| Republic Airways | 89.4% | 54 min | 1.7% | 709 |
| United Airlines | 87.3% | 74 min | 0.8% | 516 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly PIT to IAD
On-time arrival % by scheduled departure hour (local time), 2,163 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 6am–7am | 95.3% | 0.7% | 723 |
| 10am–11am | 94.0% | 0.7% | 302 |
| 1pm–2pm | 92.5% | 0.9% | 107 |
| 2pm–3pm | 79.6% | 0.9% | 218 |
| 3pm–4pm | 73.1% | 1.4% | 354 |
| 7pm–8pm | 80.5% | 4.3% | 161 |
| 8pm–9pm | 86.0% | 2.0% | 298 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on PIT 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) | 88.6% | +0.4 pts | 0.0% | 44 |
| Christmas & New Year (Dec 20 - Jan 3) | 85.7% | -2.5 pts | 0.0% | 70 |
| Summer peak (Jun 15 - Aug 15) | 83.9% | -4.3 pts | 4.3% | 376 |
| All other days | 88.2% | — | 0.7% | 1,673 |
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).