Find a better flight
US domestic flights only at this time
Filter by
Filters apply to trips matching your advanced settings.
Departing flights
Ranking & search details
7 nonstop, 8 with 1 connection · ranked by overall best · 13 hidden by your Most reliable time setting (they leave at other times of day)
Most reliable time: overnight departures (10 PM–5 AM), the window with the best on-time odds for this trip. Turn off “Most reliable” under Departure time in Advanced settings to see every time.
2 matching trips
Why this is our top pick
- This overnight flight leaves in the most reliable time of day on this route: its best departures have a 78% reliability rating vs 72% for afternoon departures.
- United trips we compared arrive on time 77% of the time on average, 2 points more often than American (75%).
- Compared with the next-best option (Republic 3459 on the Embraer E175), it arrives on time 2 points more often.
- Legroom was comparable across the flights we compared (30 in), so it didn't set them apart.
Aircraft and legroom reflect the planes each flight has flown recently. Airlines can swap planes and seat maps change, so check the airline’s seat map when you book.
IAD → PWM
Dulles to Portland: 821 nonstop flights a year
On time (12 months)
86%
Cancelled
2.2%
avg delay 14 min
Best time to leave
Before 9 AM
95% on time vs 74% after 9 PM
Most reliable airline
Republic
84% chance on time
Fares open on our travel partner (Aviasales). Pick the flight number you chose here.
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- Republic Airways (sold as American Eagle, Delta Connection or United Express)84%
810 flights · 85% on time as flown · 2.2% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM95%
187 flights · avg delay 3 min
- Noon to 3 PM90%
295 flights · avg delay 7 min
- 3 to 6 PM79%
202 flights · avg delay 18 min
- After 9 PM74%
137 flights · avg delay 39 min
Best day: Tuesday (90%). Worst: Thursday (84%).
Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure