Best Time to Fly SAN to IAD: On-Time Stats by Hour & Airline
San Diego International → Washington Dulles International
Data through July 2026 · Last updated October 18, 2026
1,402 flights were scheduled from San Diego (SAN) to Washington (IAD) in the last 12 months, and 88.2% of those that flew arrived on time, 10.6 points above the US average of 77.6%.
Among 2 airlines, United Airlines led with 88.6% on time and Alaska Airlines was last with 87.1%.
Over 24 months, Tuesday was the most reliable day (90% on time) and July the worst month (74%).
The cancellation rate was 0.7% (US average 1.8%).
SAN 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 | 88.6% | 84 min | 0.7% | 1,041 |
| Alaska Airlines | 87.1% | 58 min | 0.8% | 361 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly SAN to IAD
On-time arrival % by scheduled departure hour (local time), 2,857 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 7am–8am | 85.3% | 0.0% | 70 |
| 8am–9am | 81.6% | 0.5% | 963 |
| 9am–10am | 89.0% | 0.8% | 238 |
| 10am–11am | 72.1% | 0.0% | 167 |
| 12pm–1pm | 84.9% | 0.0% | 558 |
| 1pm–2pm | 95.1% | 0.6% | 168 |
| 2pm–3pm | Limited data | 2 | |
| 9pm–10pm | 87.3% | 0.7% | 541 |
| 10pm–11pm | 88.5% | 1.3% | 150 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on SAN 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) | 94.2% | +7.6 pts | 0.0% | 52 |
| Christmas & New Year (Dec 20 - Jan 3) | 75.8% | -10.8 pts | 0.0% | 120 |
| Summer peak (Jun 15 - Aug 15) | 77.1% | -9.5 pts | 0.4% | 494 |
| All other days | 86.6% | — | 0.6% | 2,191 |
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).