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Airport · 12 months to July 2026
St Louis Lambert International: delays and on-time record
St. Louis, Missouri
BTS: A flight is counted as on time if it arrived less than 15 minutes after its scheduled time. Only carriers with at least 0.5 percent of domestic scheduled passenger revenue report. Data through July 2026; this is a monthly history, not live airport status.
St Louis Lambert International (STL) in St. Louis, Missouri had 63,318 scheduled domestic departures by reporting carriers in the 12 months to July 2026, about 174 a day, on 65 routes.
74.1% of those flights left the gate less than 15 minutes late, 2.0 points below the national departure figure of 76.1%. Flights arriving at STL were on time 77.7% of the time, 1.7 points above the national arrival figure of 76.0%.
1.3% of scheduled departures were cancelled (national: 1.8%), and the average departure delay, counting early and on-time departures as zero, was 17.6 min.
Southwest Airlines is the largest reporting carrier at STL with 62% of departures. Among carriers with at least 633 departures, Delta Air Lines had the highest on-time arrival share for its STL departures (86.6%) and SkyWest Airlines the lowest (68.1%).
On-time departures are down 4.9 points on the previous 12 months (79.0%).
Of the delay minutes that carriers assigned to a BTS cause category for flights leaving STL, late-arriving aircraft 45%, air carrier 31% and national aviation system 20%.
- On time 76.8%
- Arrived 15+ minutes late 21.7%
- Cancelled 1.3%
- Diverted 0.3%
As origin and as destination, against the nation
| Measure | Departures from STL | Arrivals at STL | All reported flights | STL departures, previous 12 months |
|---|---|---|---|---|
| Departed on time (less than 15 min late) | 74.1% | 73.8% | 76.1% | 79.0% |
| Arrived on time | 76.8% | 77.7% | 76.0% | 80.1% |
| Cancelled | 1.3% | 1.3% | 1.8% | 1.3% |
| Diverted | 0.3% | 0.2% | 0.3% | 0.2% |
| Average departure delay (late minutes only) | 17.6 min | 15.9 min | 17.4 min | 14.1 min |
| Arrival delay minutes per 100 flights | 1,596 | 1,383 | 1,684 | 1,321 |
| Scheduled flights | 63,318 | 63,316 | 7,043,858 | 64,824 |
12 months to July 2026. The first column follows flights that left STL; the second follows flights that landed there. Year on year, on-time departures moved −4.9 pts.
Airlines at STL
| Reporting carrier | Flights | Share | On time | Avg arrival delay | Cancelled |
|---|---|---|---|---|---|
| WN Southwest Airlines | 39,473 | 62% | 76.1% | 7.0 min | 0.6% |
| AA American Airlines | 5,879 | 9% | 79.6% | 11.3 min | 2.1% |
| DL Delta Air Lines | 5,325 | 8% | 86.6% | -1.7 min | 1.6% |
| YX Republic Airline | 3,172 | 5% | 75.7% | 6.1 min | 4.5% |
| UA United Airlines | 2,356 | 4% | 74.4% | 12.1 min | 1.1% |
| OO SkyWest Airlines | 2,276 | 4% | 68.1% | 22.9 min | 2.6% |
| MQ Envoy Air | 1,604 | 3% | 75.9% | 9.8 min | 2.5% |
| F9 Frontier Airlines | 1,398 | 2% | 70.3% | 17.7 min | 2.1% |
| OH PSA Airlines | 894 | 1% | 70.7% | 17.1 min | 5.1% |
| AS Alaska Airlines | 861 | 1% | 81.9% | 0.1 min | 1.2% |
| NK Spirit Airlines | 80 | 0% | 71.3% | 21.9 min | 1.3% |
Departures from STL by reporting carrier, ordered by flights; on time means the flight reached its destination less than 15 minutes late. Green is at or above the airport's overall share of 76.8%. Carriers fly different routes at different hours, so the rows are not a like-for-like test.
Busiest routes from STL
| Route | Cities | Flights | On time | Avg arrival delay | Cancelled |
|---|---|---|---|---|---|
| STL–ATL | St. Louis to Atlanta | 3,684 | 83.1% | -0.3 min | 1.7% |
| STL–DEN | St. Louis to Denver | 3,676 | 75.1% | 10.4 min | 0.3% |
| STL–ORD | St. Louis to Chicago | 3,090 | 69.9% | 19.0 min | 3.6% |
| STL–LGA | St. Louis to New York | 2,624 | 71.6% | 8.9 min | 3.6% |
| STL–MCO | St. Louis to Orlando | 2,520 | 76.9% | 6.6 min | 0.9% |
| STL–DCA | St. Louis to Washington | 2,416 | 70.9% | 12.3 min | 2.6% |
| STL–DFW | St. Louis to Dallas/Fort Worth | 2,381 | 72.4% | 19.0 min | 3.3% |
| STL–PHX | St. Louis to Phoenix | 2,315 | 74.2% | 13.1 min | 0.5% |
| STL–LAS | St. Louis to Las Vegas | 2,094 | 75.2% | 8.5 min | 0.6% |
| STL–DAL | St. Louis to Dallas | 1,952 | 74.3% | 8.5 min | 1.5% |
| STL–MSP | St. Louis to Minneapolis | 1,936 | 79.6% | 6.7 min | 0.9% |
| STL–DTW | St. Louis to Detroit | 1,894 | 80.3% | 6.3 min | 1.2% |
| STL–CLT | St. Louis to Charlotte | 1,835 | 82.5% | 4.3 min | 1.4% |
| STL–MDW | St. Louis to Chicago | 1,704 | 78.9% | 3.9 min | 1.2% |
| STL–BOS | St. Louis to Boston | 1,611 | 68.4% | 14.5 min | 1.7% |
| STL–PHL | St. Louis to Philadelphia | 1,602 | 78.8% | 8.1 min | 1.4% |
| STL–HOU | St. Louis to Houston | 1,539 | 78.0% | 3.0 min | 0.3% |
| STL–BNA | St. Louis to Nashville | 1,287 | 81.7% | 2.6 min | 0.6% |
| STL–BWI | St. Louis to Baltimore | 1,279 | 78.9% | 3.8 min | 1.3% |
| STL–TPA | St. Louis to Tampa | 1,228 | 79.4% | 6.4 min | 0.6% |
| STL–MIA | St. Louis to Miami | 1,170 | 81.3% | 1.1 min | 0.7% |
| STL–EWR | St. Louis to Newark | 1,075 | 77.1% | 5.2 min | 4.7% |
| STL–LAX | St. Louis to Los Angeles | 1,027 | 73.1% | 11.8 min | 0.3% |
| STL–MCI | St. Louis to Kansas City | 1,020 | 75.4% | 7.8 min | 0.3% |
| STL–RSW | St. Louis to Fort Myers | 1,007 | 78.6% | 5.9 min | 0.5% |
| STL–SLC | St. Louis to Salt Lake City | 990 | 86.4% | 3.8 min | 0.9% |
| STL–AUS | St. Louis to Austin | 972 | 75.5% | 6.2 min | 0.4% |
| STL–SEA | St. Louis to Seattle | 884 | 78.2% | 2.6 min | 0.9% |
| STL–FLL | St. Louis to Fort Lauderdale | 828 | 73.8% | 9.7 min | 0.5% |
| STL–OMA | St. Louis to Omaha | 825 | 77.3% | 6.9 min | 0.1% |
| STL–SFO | St. Louis to San Francisco | 761 | 59.8% | 23.6 min | 0.8% |
| STL–MSY | St. Louis to New Orleans | 733 | 83.4% | 1.5 min | 0.1% |
| STL–CLE | St. Louis to Cleveland | 698 | 81.5% | 5.6 min | 0.3% |
| STL–MKE | St. Louis to Milwaukee | 685 | 81.8% | 3.7 min | 0.7% |
| STL–CMH | St. Louis to Columbus | 675 | 81.2% | 3.3 min | 0.3% |
| STL–RDU | St. Louis to Raleigh/Durham | 655 | 80.8% | 5.4 min | 0.2% |
| STL–SAT | St. Louis to San Antonio | 548 | 79.9% | 0.7 min | 0.2% |
| STL–JAX | St. Louis to Jacksonville | 507 | 78.3% | 6.8 min | 0.2% |
| STL–PIT | St. Louis to Pittsburgh | 500 | 79.2% | 6.5 min | 0.0% |
| STL–SAN | St. Louis to San Diego | 473 | 77.0% | 4.9 min | 0.2% |
| STL–IAH | St. Louis to Houston | 423 | 79.7% | -0.6 min | 1.2% |
| STL–OKC | St. Louis to Oklahoma City | 412 | 81.3% | 1.3 min | 1.2% |
| STL–DSM | St. Louis to Des Moines | 403 | 80.9% | 0.7 min | 0.5% |
| STL–ICT | St. Louis to Wichita | 403 | 80.4% | 4.0 min | 1.0% |
| STL–LIT | St. Louis to Little Rock | 403 | 84.4% | 1.4 min | 1.2% |
| STL–TUL | St. Louis to Tulsa | 403 | 81.4% | 3.2 min | 1.0% |
| STL–SRQ | St. Louis to Sarasota/Bradenton | 349 | 71.6% | 11.6 min | 0.6% |
| STL–SMF | St. Louis to Sacramento | 331 | 79.5% | 5.4 min | 0.0% |
| STL–ECP | St. Louis to Panama City | 315 | 74.6% | 7.6 min | 0.3% |
| STL–PNS | St. Louis to Pensacola | 216 | 84.3% | 3.0 min | 0.0% |
| STL–BUR | St. Louis to Burbank | 192 | 77.1% | 4.9 min | 0.0% |
| STL–CHS | St. Louis to Charleston | 160 | 79.4% | 4.5 min | 0.0% |
| STL–VPS | St. Louis to Valparaiso | 138 | 71.7% | 9.4 min | 0.0% |
The 53 busiest of 65 routes with reported flights. Routes with at least 10 flights a month have their own page.
Month by month
By scheduled departure hour
Among hours with at least 1,266 departures, 5 am to 6 am had the highest on-time share (92.9% of 3,299 flights) and 9 pm to 10 pm the lowest (51.8% of 2,085).
Delay causes
Cancellations by reported reason (818 in the period): air carrier 20%, weather 65%, national aviation system 15%, security 0%.
Checkpoint volumes
TSA publishes daily checkpoint passenger counts for the country as a whole, not for STL on its own. The national series through September 2026 is on the checkpoint volumes page.
Questions and answers
How often do flights leave STL on time?
74.1% of the 63,318 scheduled domestic departures in the 12 months to July 2026 left less than 15 minutes late; the national figure was 76.1%. 1.3% were cancelled.
How often do flights arrive at STL on time?
77.7% of 63,316 scheduled arrivals were on time by the BTS definition, against 76.0% nationally.
Which airline has the highest on-time share at STL?
Counting departures from STL and whether they reached their destination on time, Delta Air Lines had the highest share (86.6% of 5,325 flights), then Alaska Airlines (81.9%) and American Airlines (79.6%). Carriers fly different routes at different hours, so the figures are not a like-for-like test.
What causes delays at STL?
For departures from STL that reached their destination 15 or more minutes late, carriers attributed the delay minutes as follows: late-arriving aircraft 45%, air carrier 31%, national aviation system 20%, extreme weather 5%, security 0%.
What time of day has the highest on-time share at STL?
Departures scheduled from 5 am to 6 am local time left on time 92.9% of the time, the highest of any hour with enough flights to compare; 9 pm to 10 pm was lowest at 51.8%.
Is it getting better?
On-time departures for the 12 months to July 2026 were 74.1%, down 4.9 points on the previous 12 months (79.0%). The monthly chart shows each of the last 36 months, and each month has its own page.
Does this page show today's delays at STL?
No. BTS publishes on-time records about two months after the month ends, so this page is a monthly history through July 2026. For live conditions use the FAA airport status service or your airline.
Provenance
Source: Bureau of Transportation Statistics, Reporting Carrier On-Time Performance (1987 to present), monthly files August 2023 to July 2026; airport name from the BTS airport lookup table. US government works in the public domain. Domestic scheduled flights by reporting carriers only: international flights, charters and smaller carriers are not in the source. Totals and averages only; no individual flight or aircraft is identified. See the methodology; report processing errors through corrections.