BTS DATA COMPLETE THROUGH JUNE 2026HISTORICAL ODDS · NOT LIVE FLIGHT STATUS
DelayOddsKnow the route before you book
SFOSTL

San Francisco, CA (SFO) to St. Louis, MO (STL) flight delay odds

Historically, 64.9% of scheduled reportable flights on this direction arrived on time in July 2025–June 2026. The sample includes 781 flights.

HISTORICAL ROUTE SIGNALVariable
64.9%arrived on time
23.4%30+ min late
0.9%cancelled
781scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late12.5%all scheduled flights
120+ minutes late3.2%all scheduled flights
Diverted0.4%did not reach as scheduled
Average arrival+15.2 mincompleted flights

When is this route most reliable?

The same route can behave differently through the day. These are scheduled departure windows, not actual departure times. Small time windows with fewer than 40 flights are withheld.

Departure windowFlightsOn time30+ minCancelled
Late morning44568.1%18.0%0.4%
Afternoon24055.0%36.2%1.2%
Night7368.5%20.5%2.7%

Weekday comparison

Day-of-week results use at least 30 scheduled flights per row. Look for broad patterns, not tiny percentage differences.

DayFlightsOn time30+ minCancelled
Monday11656.0%29.3%0.9%
Tuesday10671.7%19.8%0.0%
Wednesday11361.9%23.9%0.0%
Thursday12060.0%25.8%0.8%
Friday11465.8%20.2%0.0%
Saturday9174.7%15.4%4.4%
Sunday12166.9%27.3%0.8%

Airline comparison

Marketing-carrier results make codeshare flights easier to compare as travelers buy them. Dedicated route-airline reports require at least 160 flights.

AirlineFlightsOn time30+ minCancelled
Southwest Airlines34248.8%35.1%0.0%
SkyWest Airlines23575.3%16.6%2.6%
United Airlines20479.9%11.8%0.5%

Monthly trend

Month-by-month results show whether a twelve-month average hides an unusual period.

MonthFlightsOn time30+ minCancelled
July 20258363.9%25.3%1.2%
August 20256277.4%9.7%0.0%
September 20256071.7%16.7%0.0%
October 20256271.0%17.7%0.0%
November 20255752.6%28.1%0.0%
December 20256160.7%24.6%0.0%
January 20266987.0%7.2%4.3%
February 20265969.5%13.6%0.0%
March 20266078.3%10.0%1.7%
April 20267753.2%39.0%2.6%
May 20267146.5%46.5%0.0%
June 20266050.0%36.7%0.0%

What drove reported delay minutes?

BTS cause minutes are reported for qualifying delayed flights. These shares describe recorded delay minutes—not the chance that a particular cause will affect your next flight.

Airline26.8%
Late aircraft57.3%
National airspace15.7%
Weather0.2%
Security0.0%
This is historical evidence, not a forecast.

Weather, schedules and operations change. For a trip you have already booked, use the airline or airport for live status.