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Ranking & search details
2 nonstop, 38 with 1 connection, 6 with 2 · ranked by overall best · 19 hidden by your Most reliable time setting (they leave at other times of day) · showing the top 3
Most reliable time: morning departures (5–11 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.
Fares seen on this date: nonstop from 263 · any route from 181 (recent searches, one way, per person; each card opens the live price)
27 matching trips
Why this is our top pick
- This morning flight leaves in the most reliable time of day on this route: its best departures have an 80% reliability rating vs 61% for afternoon departures.
- United trips we compared arrive on time 78% of the time on average, 4 points more often than Delta and American (74%).
- It has the same 30 in of legroom as the next-best option (United 469 + United 1549 on the Boeing 737-800 or Airbus A319); it arrives on time 12 points more often.
5:00 AM11:33 AMSAT → IAD
United · UA 469 / UA 1549
5h 33m1 stop
1h 18m in IAH
One ticket
84%arrive on time93% connections madeCheck fares
5:15 AM1:29 PMSAT → IAD
Southwest + United · WN 4166 / UA 646
7h 14m1 stop
2h 17m in MCO
Separate tickets
88%arrive on time96% connections made
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.
SAT → IAD
San Antonio to Dulles: 636 nonstop flights a year
On time (12 months)
93%
Cancelled
0.6%
avg delay 7 min
Best time to leave
Before 9 AM
96% on time vs 86% 9 AM to noon
Most reliable airline
United
93% chance on time
Lowest nonstop fare seen in the next two months: $263 (United 471 on 2026-11-29). 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.
- United Airlines93%
636 flights · 93% on time as flown · 0.6% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM96%
313 flights · avg delay 4 min
- 9 AM to noon86%
95 flights · avg delay 16 min
- Noon to 3 PM92%
228 flights · avg delay 6 min
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