St. Louis, MO · Airport profile
STL
St. Louis Lambert International Airport
79.1% of departures from STL arrived on time across 198,650 flights, July 2023 – July 2026. The weakest hour is 10 PM, at 62.3%. Late-arriving aircraft accounts for the most delay minutes.
STL right now
Live conditions where a permitted source publishes them, and the historical record where none does.
Aviation weather is not currently a factor.
Minimal operational impact. Conditions are not a notable factor for operations right now.
UpdatedForecast issued 05:20Z.
UpdatedBelow 10,000 ft, so aircraft overflying at cruise are not counted. These are observations, not an operational status: a count is a floor, since receiver coverage varies and a movement between two samples can be missed.
UpdatedAircraft observations from ADSB.lol (opens in a new tab) (Katia Esposito and contributing feeders), under the ODbL 1.0 (opens in a new tab). Derived data.
FlyerIntel shows live values only where a permitted source provides them. Sections without data are left empty rather than estimated.
Airport reliability
Departures from STL, July 2023 – July 2026.
Better than 57% of major US airports covered by FlyerIntel (64 compared)
Calculated from 198,650 flights. How this is calculated
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
Why flights are cancelled at STL
Every cancellation carries a reason code filed by the airline that operated the flight. Departures, July 2023 – July 2026.
Extreme weather accounts for 67.0% of cancelled departures from STL — about 1 in every 123 scheduled departures. That is 7 points higher than the 59.5% recorded across every airport FlyerIntel covers.
Share of cancellations
Of 2,416 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
1,619 cancellations, 67.0% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
480 cancellations, 19.9% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
317 cancellations, 13.1% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
2,416 of 198,650 scheduled departures from STL were cancelled. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026 · Reason codes are each airline’s own filing, not an independent finding of fault. Shown for airports with at least 500 coded cancellations; 2,416 were recorded at STL.
Why flights run late at STL
Where US DOT attributed the delay minutes on departures from STL.
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for departures from STL. Only delays of 15 minutes or more are attributed.
Of the 41,007 departures from STL that left 15 or more minutes late and have a known inbound aircraft, 57% followed a flight that landed 15 or more minutes late. The other 43% left late even though the aircraft had come in on time or early. Across the 64 covered airports that share runs from 47% to 73%, with a median of 62%; STL’s is the 22nd lowest.
The late flight is the one the same aircraft flew into STL just before, found from the tail number in the DOT file. Airlines and hours differ from one airport to the next, so this describes the departures from STL and does not rate the airport.
An airport is only partly the author of its own delays. Late-arriving aircraft describes the national schedule arriving here more than anything about this airfield. Air traffic control covers airspace and airport capacity, which is where a congested airport shows up; only the airline category sits squarely inside the carriers’ own operation. How differently they run it is further down this page.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What weather costs at STL
Departures from STL by the weather at the airport in the hour they were scheduled to leave, July 2023 – July 2026.
9.4% of scheduled departures from STL left in an hour of bad weather. 3.5% of them were cancelled, against 0.9% in normal conditions, and 67.0% of the ones that flew arrived on time, against 80.4%. Those hours held 27% of all cancelled departures. That is about 473 more cancellations than the normal-conditions rate would give.
Cancellations were highest in snow or ice hours: 14.0% of 2,875 departures, 15.1 times the normal rate.
Airlines filed 67% of STL’s coded cancellations under extreme weather. By the weather at the airport in the scheduled hour, 27% of cancelled departures were in bad-weather hours. A code is the airline’s stated reason and an hour’s weather is what the airport reported, so the two need not match.
By weather
Scheduled departures, July 2023 – July 2026| Weather at the airport | Departures | Cancelled | Left on time | Arrived on time | Avg. departure delay |
|---|---|---|---|---|---|
| Normal conditionsVFR with no thunderstorm, snow or ice, fog, heavy rain or high wind | 163,09582.3% of all | 0.9% | 78.2% | 80.4% | 11.9 min |
| Any bad weatherIFR or LIFR, or a thunderstorm, snow or ice, fog, heavy rain or high wind | 18,6129.4% of all | 3.5%3.7 times normal | 69.2% | 67.0%13.4 points below normal | 22.1 min |
| MVFRceiling 1,000 to 3,000 feet or visibility 3 to 5 miles | 18,9679.6% of all | 2.0%2.2 times normal | 74.9% | 75.1%5.3 points below normal | 14.8 min |
| IFRceiling 500 to 999 feet or visibility 1 to under 3 miles | 8,6764.4% of all | 2.9%3.1 times normal | 72.3% | 70.4%10.0 points below normal | 19.2 min |
| LIFRceiling under 500 feet or visibility under 1 mile | 3,5031.8% of all | 4.4%4.8 times normal | 75.2% | 72.3%8.1 points below normal | 20.9 min |
| Thunderstorma thunderstorm reported at the airport | 3,7671.9% of all | 2.9%3.1 times normal | 46.6% | 45.2%35.2 points below normal | 46.6 min |
| Snow or icesnow, snow grains, ice pellets, freezing rain or freezing drizzle | 2,8751.5% of all | 14.0%15.1 times normal | 56.3% | 40.6%39.8 points below normal | 35.4 min |
| Fogfog or freezing fog reported at the airport | 7230.4% of all | 8.0%8.6 times normal | 72.2% | 66.7%13.7 points below normal | 24.9 min |
| Heavy rainheavy rain reported at the airport | 1,9861.0% of all | 2.7%2.9 times normal | 48.2% | 47.2%33.2 points below normal | 48.0 min |
| High windwind of 25 knots or more, or gusts of 30 knots or more | 3,4481.7% of all | 3.1%3.4 times normal | 65.0% | 63.1%17.3 points below normal | 26.1 min |
| Low ceilinga broken or overcast layer under 1,000 feet | 9,8595.0% of all | 1.6%1.7 times normal | 78.6% | 77.8%2.6 points below normal | 12.9 min |
| Low visibilityvisibility under 3 miles | 5,0612.6% of all | 6.5%7.1 times normal | 62.5% | 57.0%23.4 points below normal | 32.0 min |
A departure is counted in every row its hour fits, so the rows overlap and do not add up. Left on time is a departure under 15 minutes late, and arrived on time an arrival under 15 minutes late; cancelled is the share of scheduled departures. Rows with fewer than 120 departures are not scored.
This is the weather reported at STL in the hour a flight was scheduled to leave. It leaves out the weather at the destination and on the way, weather that arrived after the scheduled time, and anything else that goes wrong in a bad hour. An hour takes the worst conditions any report in it gave. Weather was matched to 99.8% of the airport’s scheduled departures; the rest left in hours with no report, or at a scheduled time the flight records cannot place exactly. Bad-weather hours are compared with normal hours at the same airport, not with what the same flights would have done in a clear sky: they also fall more often in some seasons and at some times of day.
Source: FlyerIntel analysis of US DOT BTS flight records and Iowa Environmental Mesonet weather reports · July 2023 – July 2026 · Where the weather comes from, and its limits. All covered airports side by side: What Weather Costs Each Airport.
Which airlines hold up in bad weather at STL
Cancellations by airline in hours of bad weather at STL, against the other carriers in the same months, July 2023 – July 2026.
9% of the weather-matched departures from STL left in an hour of bad weather at the airport. 3.5% of them were cancelled. That is 3.7 times the 0.9% in normal hours. Southwest Airlines flew 63% of those departures, so the airport’s figure here is largely Southwest Airlines’ own, and the carriers it is compared with are the smaller ones.
Compared with the other carriers at STL in the same months, Delta Air Lines (1.6% cancelled against 3.6% for the others; level with them in normal hours, so a bad-weather difference) cancelled the fewest in bad weather and Republic Airways (6.6% cancelled against 4.0% for the others; above them in normal hours too) the most. 2 more airlines are also clearly apart from the others.
Airlines in bad weather at STL
Scheduled departures, July 2023 – July 2026| Airline | Bad-weather departures | Cancelled | Other carriers | Normal hours |
|---|---|---|---|---|
| Delta Air Lines | 1,5638% of bad-weather | 1.6%below the others | 3.6% | 0.9%others 0.9% |
| Southwest Airlines | 11,66563% of bad-weather | 3.2%below the others | 4.3% | 0.5%others 1.6% |
| United Airlines | 8014% of bad-weather | 3.5% | 3.1% | 1.0%others 0.9% |
| American Airlines | 1,93210% of bad-weather | 4.4%above the others | 3.4% | 1.4%others 0.9% |
| Republic Airways | 7634% of bad-weather | 6.6%above the others | 4.0% | 3.2%others 0.8% |
Best first. The other carriers’ column applies their rate in each month to the airline’s own departures, so a stormy month is not held against it; the normal-hours column gives the same pair outside bad weather.
The 5 listed airlines flew 90% of the bad-weather departures at STL; a carrier under 500 is not listed. The comparison does not hold the hour of the day, the destination or the aircraft fixed, and a gap counts as clear only at 2 standard errors and 0.3 points. Republic Airways flies for Delta Air Lines, United Airlines and American Airlines and is counted as a carrier of its own here, though it shares the airport’s gates, its de-icing and often its decisions to cancel.
Source: FlyerIntel analysis of US DOT BTS flight records and Iowa Environmental Mesonet weather reports · July 2023 – July 2026 · Where the weather comes from, and its limits. All covered airports side by side: What Weather Costs Each Airport.
Turning aircraft around at STL
Time on the ground between one flight and the next of the same aircraft at STL, and what a late arrival does to the next departure, July 2023 – July 2026.
The median turn at STL is scheduled for 50 minutes on the ground and takes 57 minutes, against 56 minutes and 63 minutes across all airports. Aircraft are given less time on the ground here than at the typical airport. The 7 minutes by which the typical turn runs over its schedule are about what it is across all airports.
When the aircraft landed 15 or more minutes late (27,829 turns here, 54 minutes late on average), 59% of the turns were finished in no more than the scheduled ground time, against 68% across all airports. 80% of those flights left 15 or more minutes late, against 72%. After an aircraft that landed on time, 13% did (all airports 11%).
Given the turn lengths scheduled here, the network’s rates would give 61% finished in the schedule and 79% leaving late. STL finishes fewer late turns in the schedule than the network would, but lateness is passed on about as often. 47% of its late-inbound turns had a scheduled turn of 45 to 59 minutes, against 31% across all airports.
Turns at STL against all airports
155,483 turns, July 2023 – July 2026| Measure | STL | All airports | All airports, same turn lengths |
|---|---|---|---|
| Median scheduled turn | 50 min | 56 min | — |
| Median actual turn | 57 min | 63 min | — |
| Turns that began with an aircraft 15+ minutes late | 18% | 19% | — |
| Late turns finished within the schedule | 59% | 68% | 61% |
| Late inbound that left 15+ minutes late | 80% | 72% | 79% |
| On-time inbound that left 15+ minutes late | 13% | 11% | — |
The last column is the network’s rate at the turn lengths scheduled at STL, band by band from under 30 minutes to 3 to 6 hours. A turn finishes within the schedule when the aircraft spent no more time on the ground than the schedule gave it.
A turn pairs an aircraft’s landing at STL with its next departure from it by tail number; the aircraft is never named. These 155,483 turns are 78% of the flights that left STL in the period; the rest are an aircraft’s first flight after a long stay, flights without a usable inbound, and cancelled flights. Ground time runs from the gate. Turns under 30 minutes are kept, but most leave late even after an on-time landing. Airlines set their own turn schedules, so this describes the airlines that fly at STL and does not rate the airport.
Source: FlyerIntel analysis of US DOT BTS flight records · July 2023 – July 2026 · Airports side by side: Where a Late Aircraft Gets Its Time Back.
What sets STL apart
Where STL’s hours, months, airlines and taxi time differ most from the other airports, July 2023 – July 2026.
Flights scheduled to leave STL at 10 AM arrive on time 87.1% of the time, 4.3 points better than the 82.8% for that hour at the other airports.
10 PM is where STL falls furthest behind the rest: 62.3% of its 10 PM departures arrive on time, 9.7 points below the 72.0% for that hour elsewhere.
February treats STL better than it treats the rest of the country: 83.8% on time against 81.1% elsewhere, 2.7 points ahead.
Delta Air Lines does better out of STL than anywhere else it flies: 88.3% on time here, 82.0% on its other departures, 6.3 points apart.
Spirit Airlines’ departures from STL arrive on time 67.7% of the time, 7.8 points worse than the 75.5% the same airline manages at its other airports.
Taxi-out at STL averages 12.5 minutes, 6.3 minutes less than the 18.8 minutes elsewhere.
STL against the other airports
July 2023 – July 2026| Measure | STL | Elsewhere | Gap | Flights behind it |
|---|---|---|---|---|
| Hour: 10 AM departures | 87.1% | 82.8% | +4.3 pts | 15,268 here, 1,104,942 elsewhere |
| Hour: 10 PM departures | 62.3% | 72.0% | −9.7 pts | 4,286 here, 475,514 elsewhere |
| Month: February | 83.8% | 81.1% | +2.7 pts | 13,356 here, 1,233,353 elsewhere |
| Airline: Delta Air Lines | 88.3% | 82.0% | +6.3 pts | 16,691 here, 3,085,434 elsewhere |
| Airline: Spirit Airlines | 67.7% | 75.5% | −7.8 pts | 839 here, 620,465 elsewhere |
| Taxi-out: Departures | 12.5 min | 18.8 min | −6.3 min | 196,284 here, 17,433,825 elsewhere |
"Elsewhere" is every other covered airport together, taken from the same aggregates as this page with STL’s own flights removed (for airlines, that airline’s flights from all its other airports). Hours, months and airlines appear only where both sides have at least 120 completed flights (airlines 500) and the gap is at least 2 points and 2 standard errors; only the largest gap in each direction is shown. The taxi figure is weighted by departures and has no error estimate, so it appears from 2 minutes.
Best time to fly from STL
On-time arrival rate by scheduled local departure time: each weekday and hour, and averaged over the week.
Flights departing 5–9 AM arrived on time 89.5% of the time, against 64.3% for 9 PM–5 AM departures — a gap of 25.2 percentage points.
By day and hour
On-time arrival rate for each weekday and scheduled departure hour, in local time.
Thursday 5–6 AM was the most reliable slot at STL (94.8% on time, 1,574 flights) and Sunday 10–11 PM the least (58.7%, 1,304 flights).
Hour of departure matters more than day of the week: hourly averages sit a typical 9.1 points from the airport-wide rate, weekday averages 2.3 points.
| Hour | Monday | Tuesday | Wednesday | Thursday | Friday | Saturday | Sunday |
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On-time rate, % · stronger color, fewer on time
- 50–59
- 60–69
- 70–79
- 80–89
- 90–99
- Most reliable slot
- Least reliable slot
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · On time is arrival within 15 minutes of schedule. Cells round to whole percentages; the table shows one decimal.
Best and worst slots are named only among slots with 500+ flights, and only when the gap is larger than sampling error. Departures after 11 PM (53 flights) are not drawn: no slot in those hours has enough flights to score.
View as tableHide table
| Hour | Monday | Tuesday | Wednesday | Thursday | Friday | Saturday | Sunday |
|---|---|---|---|---|---|---|---|
| 5 AM–6 AM | 92.1% on time1,564 flights | 93.1% on time1,092 flights | 93.8% on time1,084 flights | 94.8% on time1,574 flights | 93.6% on time1,588 flights | 89.9% on time1,191 flights | 92.1% on time1,340 flights |
| 6 AM–7 AM | 88.4% on time2,164 flights | 90.2% on time2,336 flights | 92.4% on time2,319 flights | 92.1% on time2,148 flights | 88.1% on time2,162 flights | 89.6% on time2,066 flights | 89.3% on time2,121 flights |
| 7 AM–8 AM | 86.5% on time2,075 flights | 89.0% on time1,679 flights | 89.3% on time1,625 flights | 89.7% on time2,054 flights | 89.3% on time2,088 flights | 85.5% on time1,734 flights | 87.3% on time1,871 flights |
| 8 AM–9 AM | 85.7% on time2,129 flights | 89.6% on time2,317 flights | 89.6% on time2,327 flights | 89.5% on time2,107 flights | 86.9% on time2,123 flights | 86.0% on time2,008 flights | 88.7% on time2,205 flights |
| 9 AM–10 AM | 83.8% on time1,924 flights | 85.9% on time1,600 flights | 86.3% on time1,594 flights | 89.5% on time1,920 flights | 88.2% on time1,944 flights | 83.9% on time1,275 flights | 85.8% on time1,647 flights |
| 10 AM–11 AM | 84.5% on time2,110 flights | 88.3% on time2,392 flights | 89.9% on time2,409 flights | 86.4% on time2,116 flights | 86.1% on time2,065 flights | 86.1% on time2,075 flights | 87.7% on time2,251 flights |
| 11 AM–12 PM | 80.5% on time1,297 flights | 87.3% on time1,292 flights | 85.6% on time1,304 flights | 83.7% on time1,275 flights | 82.9% on time1,300 flights | 82.4% on time1,072 flights | 83.6% on time1,260 flights |
| 12 PM–1 PM | 78.3% on time1,043 flights | 85.7% on time1,112 flights | 86.3% on time1,101 flights | 81.8% on time1,018 flights | 80.1% on time1,016 flights | 78.6% on time1,031 flights | 81.7% on time1,120 flights |
| 1 PM–2 PM | 74.9% on time1,558 flights | 81.8% on time1,458 flights | 83.2% on time1,488 flights | 78.7% on time1,536 flights | 75.3% on time1,559 flights | 75.3% on time1,721 flights | 75.5% on time1,459 flights |
| 2 PM–3 PM | 75.9% on time1,802 flights | 80.4% on time1,699 flights | 79.1% on time1,709 flights | 77.8% on time1,779 flights | 74.5% on time1,811 flights | 74.5% on time1,495 flights | 76.1% on time1,760 flights |
| 3 PM–4 PM | 73.4% on time1,666 flights | 79.0% on time1,542 flights | 78.1% on time1,511 flights | 73.5% on time1,636 flights | 72.1% on time1,680 flights | 73.4% on time1,421 flights | 67.5% on time1,758 flights |
| 4 PM–5 PM | 68.8% on time1,349 flights | 70.6% on time1,356 flights | 70.4% on time1,338 flights | 67.5% on time1,346 flights | 64.7% on time1,329 flights | 67.8% on time1,287 flights | 60.8% on time1,501 flights |
| 5 PM–6 PM | 69.6% on time1,703 flights | 75.8% on time1,799 flights | 70.7% on time1,817 flights | 66.3% on time1,713 flights | 67.6% on time1,736 flights | 72.5% on time2,182 flights | 64.5% on time1,800 flights |
| 6 PM–7 PM | 72.1% on time1,834 flights | 78.0% on time2,055 flights | 76.9% on time2,098 flights | 68.7% on time1,822 flights | 68.9% on time1,780 flights | 70.5% on time1,211 flights | 65.0% on time1,813 flights |
| 7 PM–8 PM | 68.5% on time1,914 flights | 75.2% on time1,669 flights | 70.3% on time1,691 flights | 63.0% on time1,853 flights | 68.8% on time1,879 flights | 65.2% on time906 flights | 59.2% on time1,737 flights |
| 8 PM–9 PM | 69.2% on time1,564 flights | 78.7% on time1,366 flights | 77.3% on time1,421 flights | 64.8% on time1,524 flights | 70.8% on time1,555 flights | 60.6% on time717 flights | 62.6% on time1,702 flights |
| 9 PM–10 PM | 70.0% on time1,248 flights | 70.3% on time982 flights | 67.3% on time961 flights | 61.8% on time1,165 flights | 68.2% on time1,233 flights | 53.8% on time464 flights | 60.1% on time1,138 flights |
| 10 PM–11 PM | 63.6% on time767 flights | 63.3% on time213 flights | 60.1% on time180 flights | 65.9% on time784 flights | 63.3% on time867 flights | 63.0% on time222 flights | 58.7% on time1,304 flights |
By departure window
All days combinedBy departure hour
All days combined- 12 AM to 4 AM: too few flights to score
- 5 AM: 92.8% on time from 9,433 flights
- 6 AM: 90.1% on time from 15,316 flights
- 7 AM: 88.1% on time from 13,126 flights
- 8 AM: 88.1% on time from 15,216 flights
- 9 AM: 86.3% on time from 11,904 flights
- 10 AM: 87.1% on time from 15,418 flights
- 11 AM: 83.8% on time from 8,800 flights
- 12 PM: 81.9% on time from 7,441 flights
- 1 PM: 77.7% on time from 10,779 flights
- 2 PM: 76.9% on time from 12,055 flights
- 3 PM: 73.7% on time from 11,214 flights
- 4 PM: 67.1% on time from 9,506 flights
- 5 PM: 69.7% on time from 12,750 flights
- 6 PM: 71.8% on time from 12,613 flights
- 7 PM: 67.3% on time from 11,649 flights
- 8 PM: 69.5% on time from 9,849 flights
- 9 PM: 65.4% on time from 7,191 flights
- 10 PM: 62.3% on time from 4,337 flights
- 11 PM: too few flights to score
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Buckets with fewer than 120 flights are not scored.
What parking will cost
Estimated from STL's own published rates.
Estimated cost
Choose a facility and both dates to see an estimate.
Rates as published by the airport, last read 2026-08-31. Confirm before you travel.
Source: St. Louis Lambert International Airport · An estimate from published standard rates. Airports vary surcharges, oversize vehicle fees and event pricing, so confirm the price with the airport before you travel.
International arrivals
How long passport control normally takes here, hour by hour and hall by hall. This is the arrivals queue, not departure security — and it is history, not a live wait.
At Main, STL’s busiest hall, both passport queues run much the same: a typical 10 min on a US passport and 11 min on any other, rising to 25 min on a busy day. Where the two halls agree like this, CBP’s combined figure of 10 min is a fair summary of both — which is not true everywhere, and is why they are shown apart.
Terminal by terminal, across the day
| Terminal | US passports | US busy day | Other passports | Other busy day | Global Entry |
|---|---|---|---|---|---|
| Main | 10 min | 21 min | 11 min | 25 min | 9.3% of arrivals |
US passports — Main
- 12 AM–1 AM: too few records to publish
- 1 AM–2 AM: too few records to publish
- 2 AM–3 AM: too few records to publish
- 3 AM–4 AM: too few records to publish
- 4 AM–5 AM: too few records to publish
- 5 AM–6 AM: too few records to publish
- 6 AM–7 AM: too few records to publish
- 7 AM–8 AM: too few records to publish
- 8 AM–9 AM: too few records to publish
- 9 AM–10 AM: too few records to publish
- 10 AM–11 AM: too few records to publish
- 11 AM–12 PM: too few records to publish
- 12 PM–1 PM: too few records to publish
- 1 PM–2 PM: typically 16 min, 29 min on a busy day (373 days)
- 2 PM–3 PM: typically 12 min, 28 min on a busy day (337 days)
- 3 PM–4 PM: typically 9 min, 16 min on a busy day (379 days)
- 4 PM–5 PM: typically 8 min, 13 min on a busy day (322 days)
- 5 PM–6 PM: typically 9 min, 17 min on a busy day (347 days)
- 6 PM–7 PM: typically 8 min, 16 min on a busy day (289 days)
- 7 PM–8 PM: typically 10 min, 17 min on a busy day (177 days)
- 8 PM–9 PM: too few records to publish
- 9 PM–10 PM: too few records to publish
- 10 PM–11 PM: too few records to publish
- 11 PM–12 AM: too few records to publish
US citizens and lawful permanent residents, who use the US-passport lanes.
All other passports — Main
- 12 AM–1 AM: too few records to publish
- 1 AM–2 AM: too few records to publish
- 2 AM–3 AM: too few records to publish
- 3 AM–4 AM: too few records to publish
- 4 AM–5 AM: too few records to publish
- 5 AM–6 AM: too few records to publish
- 6 AM–7 AM: too few records to publish
- 7 AM–8 AM: too few records to publish
- 8 AM–9 AM: too few records to publish
- 9 AM–10 AM: too few records to publish
- 10 AM–11 AM: too few records to publish
- 11 AM–12 PM: too few records to publish
- 12 PM–1 PM: too few records to publish
- 1 PM–2 PM: typically 20 min, 33 min on a busy day (373 days)
- 2 PM–3 PM: typically 13 min, 34 min on a busy day (337 days)
- 3 PM–4 PM: typically 9 min, 21 min on a busy day (379 days)
- 4 PM–5 PM: typically 9 min, 18 min on a busy day (322 days)
- 5 PM–6 PM: typically 10 min, 22 min on a busy day (347 days)
- 6 PM–7 PM: typically 9 min, 17 min on a busy day (289 days)
- 7 PM–8 PM: typically 11 min, 20 min on a busy day (177 days)
- 8 PM–9 PM: too few records to publish
- 9 PM–10 PM: too few records to publish
- 10 PM–11 PM: too few records to publish
- 11 PM–12 AM: too few records to publish
Every other arriving passenger, including visa and visa-waiver travelers.
Hour by hour — Main
| Cleared in hour | US passports | US busy day | Other passports | Other busy day | Booths open |
|---|---|---|---|---|---|
| 1 PM–2 PM | 16 min | 29 min | 20 min | 33 min | 4 |
| 2 PM–3 PM | 12 min | 28 min | 13 min | 34 min | 4 |
| 3 PM–4 PM | 9 min | 16 min | 9 min | 21 min | 4 |
| 4 PM–5 PM | 8 min | 13 min | 9 min | 18 min | 4 |
| 5 PM–6 PM | 9 min | 17 min | 10 min | 22 min | 3 |
| 6 PM–7 PM | 8 min | 16 min | 9 min | 17 min | 4 |
| 7 PM–8 PM | 10 min | 17 min | 11 min | 20 min | 4 |
US passports: clearing in the 1 PM–2 PM hour typically takes 16 min, against 8 min in the 4 PM–5 PM hour — 8 min between the slowest and fastest of 7 measured hours.
All other passports: clearing in the 1 PM–2 PM hour typically takes 20 min, against 9 min in the 4 PM–5 PM hour — 12 min between the slowest and fastest of 7 measured hours.
The hour is when CBP processed the passenger, not when the aircraft landed — allow for the walk from the gate. Hours with fewer than 120 days of records are not listed rather than shown as an estimate, which is why a terminal’s quietest hours are usually absent. “Busy day” is the 90th percentile: one arrival in ten is worse than that. Booths are how many CBP had open, and they follow the queue rather than prevent it — the busiest hours are staffed hardest and are still the slowest.
Source: US Customs and Border Protection · 2024-08-28 to 2026-10-16 · These are CBP passport control waits for arriving international passengers — a different queue from TSA departure screening. CBP publishes them about two days in arrears, so every figure here describes what has been typical over 2024-08-28 to 2026-10-16, and none of it is a live queue or a forecast for your flight. US and non-US passengers are reported separately by CBP and are kept separate here, because they are separate halls. FlyerIntel publishes a terminal or an hour only where CBP filed at least 120 hourly records for it, and an hour-by-hour breakdown only where at least 6 hours clear that floor.
What to expect at STL
How busy the airport is through the day, from scheduled departure volume.
Scheduled departures by hour
- 12 AM: no departures
- 1 AM: no departures
- 2 AM: no departures
- 3 AM: no departures
- 4 AM: no departures
- 5 AM: about 8 departures a day
- 6 AM: about 14 departures a day
- 7 AM: about 12 departures a day
- 8 AM: about 14 departures a day
- 9 AM: about 11 departures a day
- 10 AM: about 14 departures a day
- 11 AM: about 8 departures a day
- 12 PM: about 7 departures a day
- 1 PM: about 10 departures a day
- 2 PM: about 11 departures a day
- 3 PM: about 10 departures a day
- 4 PM: about 8 departures a day
- 5 PM: about 11 departures a day
- 6 PM: about 11 departures a day
- 7 PM: about 10 departures a day
- 8 PM: about 9 departures a day
- 9 PM: about 6 departures a day
- 10 PM: about 4 departures a day
- 11 PM: fewer than one departure a day
The busiest hour is 10 AM, with about 14 departures a day, against roughly 6 at 9 PM. That peak is also more punctual than a typical hour here, despite the volume.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Taxi-out runs from gate to wheels-up, averaged over departures and weighted by hour. Taxi-in runs from touchdown to gate.
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Sunday the least, a gap of 7.1 percentage points.
By month
- Jan: 80.3% on time
- Feb: 83.8% on time
- Mar: 79.1% on time
- Apr: 81.0% on time
- May: 75.4% on time
- Jun: 72.8% on time
- Jul: 70.0% on time
- Aug: 79.3% on time
- Sep: 84.2% on time
- Oct: 83.8% on time
- Nov: 84.8% on time
- Dec: 79.1% on time
July is historically the weakest month and November the strongest, a spread of 14.8 percentage points.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026
Airlines at STL
Departure performance by operating carrier. Regional flights are reported by the carrier that operated them, not by the mainline brand.
| Carrier | Departures | On time | Cancelled | Median delay |
|---|---|---|---|---|
| Southwest Airlines WN | 125,341 | 78.1% | 0.82% | -4 min |
| American Airlines AA | 19,572 | 79.8% | 1.73% | -7 min |
| Delta Air Lines DL | 16,881 | 88.3% | 0.97% | -13 min |
| United Airlines UA | 8,450 | 74.8% | 1.21% | -3 min |
| Republic Airways YX | 7,974 | 83.7% | 3.61% | -12 min |
| Envoy Air MQ | 5,231 | 77.4% | 2.10% | -6 min |
| SkyWest Airlines OO | 3,930 | 72.7% | 1.98% | -3 min |
| Frontier Airlines F9 | 3,728 | 72.8% | 2.28% | -7 min |
| Alaska Airlines AS | 2,520 | 82.3% | 1.03% | -7 min |
| Endeavor Air 9E | 2,158 | 86.6% | 3.61% | -15 min |
| PSA Airlines OH | 1,998 | 77.9% | 4.80% | -9 min |
| Spirit Airlines NK | 867 | 67.7% | 3.11% | -2 min |
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Carriers with fewer than 500 departures are not listed.
Routes from STL
Ranked by FlyerIntel Route Reliability Score.
Most reliable
Least reliable
Busiest routes
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Only routes with at least 10,000 flights are ranked.
Reliability over time
On-time arrival rate for departures, by month.
- July 2023: 67.3% on time from 5,495 flights
- August 2023: 77.5% on time from 5,506 flights
- September 2023: 81.1% on time from 5,346 flights
- October 2023: 83.7% on time from 5,703 flights
- November 2023: 87.3% on time from 5,245 flights
- December 2023: 82.2% on time from 5,270 flights
- January 2024: 74.0% on time from 4,935 flights
- February 2024: 84.2% on time from 4,603 flights
- March 2024: 79.9% on time from 5,451 flights
- April 2024: 81.5% on time from 5,444 flights
- May 2024: 70.9% on time from 5,656 flights
- June 2024: 76.3% on time from 5,825 flights
- July 2024: 69.5% on time from 6,029 flights
- August 2024: 80.7% on time from 5,749 flights
- September 2024: 87.7% on time from 5,496 flights
- October 2024: 88.9% on time from 5,762 flights
- November 2024: 86.9% on time from 5,263 flights
- December 2024: 81.2% on time from 5,384 flights
- January 2025: 84.2% on time from 4,717 flights
- February 2025: 82.4% on time from 4,419 flights
- March 2025: 82.1% on time from 5,379 flights
- April 2025: 80.6% on time from 5,439 flights
- May 2025: 78.0% on time from 5,628 flights
- June 2025: 73.0% on time from 5,733 flights
- July 2025: 71.7% on time from 5,855 flights
- August 2025: 79.7% on time from 5,539 flights
- September 2025: 83.8% on time from 5,321 flights
- October 2025: 78.5% on time from 5,611 flights
- November 2025: 80.1% on time from 5,202 flights
- December 2025: 74.0% on time from 5,359 flights
- January 2026: 83.1% on time from 4,683 flights
- February 2026: 84.9% on time from 4,484 flights
- March 2026: 75.3% on time from 5,400 flights
- April 2026: 80.8% on time from 5,156 flights
- May 2026: 77.5% on time from 5,375 flights
- June 2026: 69.0% on time from 5,463 flights
- July 2026: 71.5% on time from 5,725 flights
Over the most recent 12 months (2025-08 to 2026-07), departures from STL arrived on time 78.0% of the time, against 81.3% in the 12 months before — declining by 3.3 percentage points.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026
Data and sources
Historical statistics
Every historical figure on this page is calculated by FlyerIntel from US DOT Bureau of Transportation Statistics on-time performance records covering July 2023 – July 2026, comprising 198,650 departures from STL. A flight counts as delayed when it arrives 15 or more minutes after schedule.
Full methodology · All data sources
Related research: The Day After the Holiday · The Least Reliable Hour of the Week · The Best Major Airports for a Tight Connection · Which Months Cancel the Most Flights
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<a href="https://flyerintel.com/airports/stl/"><img src="https://flyerintel.com/badge/airport/stl/" alt="St. Louis Lambert International Airport on-time performance, from FlyerIntel"></a>Live conditions
Aviation weather comes from the NOAA Aviation Weather Center. Operational events come from the FAA where available. FlyerIntel shows the age of every live value and does not display data it cannot currently retrieve.
Latest observation for STL: METAR KSTL 180751Z AUTO 12004KT 10SM CLR 07/03 A3046 RMK AO2 SLP315 T00670028 (issued ).