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

St. Louis, MO (STL) to San Diego, CA (SAN) flight delay odds

74.5% of 474 official scheduled STL-to-SAN flights arrived on time; 14.8% arrived at least 30 minutes late and 0.2% were cancelled during July 2025–June 2026.

Source: U.S. Bureau of Transportation Statistics · Reporting window: July 2025–June 2026 · Updated September 16, 2026

HISTORICAL ROUTE SIGNALGenerally reliable
74.5%arrived on time
14.8%30+ min late
0.2%cancelled
474scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late5.3%all scheduled flights
120+ minutes late1.3%all scheduled flights
Diverted0.2%did not reach as scheduled
Average arrival+6.6 mincompleted flights

Which departure time was most reliable for STL to SAN?

Among qualifying STL-to-SAN departure window results, Early morning had the highest on-time rate: 85.9% of 128 flights. Evening was lowest at 48.5% across 66 flights.

Departure windowFlightsOn time30+ minCancelled
Early morning12885.9%5.5%0.8%
Late morning13984.9%8.6%0.0%
Afternoon13667.6%16.2%0.0%
Evening6648.5%37.9%0.0%

Which weekday was most reliable for STL to SAN?

Among qualifying STL-to-SAN weekday results, Tuesday had the highest on-time rate: 83.3% of 60 flights. Wednesday was lowest at 66.7% across 57 flights.

DayFlightsOn time30+ minCancelled
Monday6368.3%15.9%1.6%
Tuesday6083.3%10.0%0.0%
Wednesday5766.7%12.3%0.0%
Thursday6275.8%9.7%0.0%
Friday6876.5%10.3%0.0%
Saturday7979.7%16.5%0.0%
Sunday8570.6%24.7%0.0%

Which airline was most reliable for STL to SAN?

Only Southwest Airlines met the STL-to-SAN airline threshold: 74.5% of 474 scheduled flights arrived on time during July 2025–June 2026.

AirlineFlightsOn time30+ minCancelled
Southwest Airlines47474.5%14.8%0.2%

Which month was most reliable for STL to SAN?

Among qualifying STL-to-SAN month results, April 2026 had the highest on-time rate: 91.2% of 34 flights. June 2026 was lowest at 57.9% across 38 flights.

MonthFlightsOn time30+ minCancelled
July 20253959.0%25.6%0.0%
August 20253663.9%22.2%0.0%
September 20253476.5%17.6%0.0%
October 20255771.9%17.5%0.0%
November 20254877.1%14.6%0.0%
December 20254665.2%21.7%0.0%
January 20263585.7%8.6%0.0%
February 20263577.1%5.7%0.0%
March 20263686.1%8.3%2.8%
April 20263491.2%5.9%0.0%
May 20263688.9%0.0%0.0%
June 20263857.9%23.7%0.0%

What drove STL to SAN delay minutes?

Late aircraft was the largest recorded STL-to-SAN delay category, accounting for 45.6% of 5,618 BTS-attributed delay minutes during July 2025–June 2026.

Airline25.5%
Late aircraft45.6%
National airspace21.6%
Weather7.3%
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.