Route on-time record
SFO to STL: most on-time flights and the best time to fly
San Francisco (San Francisco International Airport) to St Louis (St. Louis Lambert International Airport). 803 nonstop flights in Jun 2025 to May 2026, 68% arrived within 15 minutes and 0.9% were cancelled. The most reliable flight number was SkyWest 5739 at 11:20 PM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
SFO → STL
San Francisco to St Louis: 803 nonstop flights a year
On time (12 months)
68%
Cancelled
0.9%
avg delay 21 min
Best time to leave
Before 9 AM
94% on time vs 49% noon to 3 PM
Most reliable airline
United
77% chance on time
Fares open on our travel partner (Aviasales). Pick the flight number you chose here.
Most reliable nonstop flights
Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.
#1 · SkyWest 5739 · sold as United Express, Delta Connection, American Eagle or Alaska
11:20 PM → 5:50 AM4h 30m nonstop
Local times, typical schedule. Last flown 2026-05-20.
76%
chance on time
- On time (history)
- 72%
- Cancelled
- 2.7%
- Avg arrival delay
- 26 min
- Arrived on time 72% of the time (36 flights, Jun 2025 to May 2026).
- Departs outside SFO's trouble window (7 AM to 1 PM, when 60% of its 334 ground stops and delay programs started).
- 77% of its delay minutes came from the plane arriving late from an earlier flight.
Limited track record · 36 flights
Find 11:20 PM flight fares Opens this date on Aviasales#2 · United 2090
12:12 PM → 6:17 PM4h 05m nonstop
Local times, typical schedule. Last flown 2026-05-31.
71%
chance on time
- On time (history)
- 73%
- Cancelled
- 0.0%
- Avg arrival delay
- 14 min
- Arrived on time 73% of the time (11 flights, Jun 2025 to May 2026).
- Leaves in this route's least on-time window (Noon to 3 PM: 49% on time; Before 9 AM: 94%).
- Departs inside SFO's trouble window: 60% of its 334 ground stops and delay programs started between 7 AM and 1 PM.
- 93% of its delay minutes came from the plane arriving late from an earlier flight.
Limited track record · 11 flights
Find United 2090 fares Opens this date on Aviasales#3 · SkyWest 6046 · sold as United Express, Delta Connection, American Eagle or Alaska
12:00 PM → 6:24 PM4h 24m nonstop
Local times, typical schedule. Last flown 2026-05-20.
70%
chance on time
- On time (history)
- 69%
- Cancelled
- 1.9%
- Avg arrival delay
- 19 min
- Arrived on time 69% of the time (52 flights, Jun 2025 to May 2026).
- Leaves in this route's least on-time window (Noon to 3 PM: 49% on time; Before 9 AM: 94%).
- Departs inside SFO's trouble window: 60% of its 334 ground stops and delay programs started between 7 AM and 1 PM.
Limited track record · 52 flights
Find 12:00 PM flight fares Opens this date on Aviasales#4 · Southwest 4219
12:15 PM → 6:05 PM3h 55m nonstop
Local times, typical schedule. Last flown 2026-05-31.
30%
chance on time
- On time (history)
- 13%
- Cancelled
- 0.0%
- Avg arrival delay
- 73 min
- Arrived on time 13% of the time (47 flights, Jun 2025 to May 2026).
- Never cancelled in 47 scheduled flights.
- Leaves in this route's least on-time window (Noon to 3 PM: 49% on time; Before 9 AM: 94%).
- Departs inside SFO's trouble window: 60% of its 334 ground stops and delay programs started between 7 AM and 1 PM.
Limited track record · 47 flights
Find Southwest 4219 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- United Airlines77%
226 flights · 80% on time as flown · 0.6% cancel
- SkyWest Airlines (sold as United Express, Delta Connection, American Eagle or Alaska)75%
235 flights · 78% on time as flown · 1.9% cancel
- Southwest Airlines56%
342 flights · 54% on time as flown · 0.3% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM94%
32 flights · avg delay 3 min
- 9 AM to noon72%
477 flights · avg delay 16 min
- Noon to 3 PM49%
158 flights · avg delay 34 min
- 3 to 6 PM76%
41 flights · avg delay 42 min
- After 9 PM70%
95 flights · avg delay 19 min
Best day: Saturday (82%). Worst: Monday (64%).
On time by month
All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.
What delays this route
- Late-arriving aircraft56%
- Airline (crew, maintenance, boarding)28%
- Air traffic control and airport volume16%
Share of delay minutes by the cause airlines report to the US DOT.
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
SFO to STL questions
- What time of day is best to fly SFO to STL?
- Before 9 AM: 94% of flights arrived on time, against 49% for departures noon to 3 PM. Later flights inherit delays from earlier ones, so the first departures of the day usually run best.
- Which airline is most on time from SFO to STL?
- United, with a season-adjusted 77% chance of operating and arriving on time over 226 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
- What is the worst month for delays on SFO to STL?
- November (62% on time); the best was January (84%), averaged over Jun 2023 to May 2026.
- Is this a prediction for my flight?
- No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.
More routes from SFO
- STL to SFO (return)
- SFO to LAX 76%
- SFO to SEA 74%
- SFO to JFK 80%
- SFO to SAN 68%
- SFO to LAS 76%
- SFO to ORD 77%
- SFO to DEN 76%
- SFO to SNA 81%
- SFO to PHX 76%
- SFO to BOS 78%
- SFO to EWR 76%
- SFO to DFW 75%
Most on-time flights from SFO on every route →
Live status: FAA delays and ground stops