Airport month record
STLJAN
St. Louis Lambert International in January 2026
- Departures
- 4,683
- Month
- January 2026
- National, same month
- 79.2%
- Carriers
- 10
Historical statistics for January 2026, not live status or a forecast for this year’s January. For today’s conditions at STL, see live FAA status.
STL in January carries a cancellation problem, not just a delay problem: 3.5% of scheduled flights never operate, against 4.7% nationally. Of the ones that do fly, more than four flights in five arrive on time, worth a B− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 4,683 flights, of which American Airlines flew 366 at 84.5% on time.
Key figures
On time
83.1%
Arrivals under 15 minutes late, of 4,511 completed departures
Avg delay
74 min
Across delayed arrivals only, not all flights
Cancelled
3.46%
Nationally in January: 4.71%
Whole year
78.0%
STL across all twelve months
These figures cover 4,683 departures from St. Louis Lambert International in January 2026. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.
Against the year
January next to STL's other months
Against STL's own year, January ran 5 points better than the twelve-month rate of 78.0%, which makes it number three of twelve months, best first. Cancellations are where January stands out: 3.46% of scheduled departures were called off, 2.7 times the airport's rate across the year. Either side of it, December ran 74.0% on time and February 84.9%, so a trip moved by a few weeks would have landed in a worse stretch.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| July 2025 | 5,855 | 71.7% | 73 min | 1.57% | C |
| August 2025 | 5,539 | 79.7% | 71 min | 0.96% | B+ |
| September 2025 | 5,321 | 83.8% | 58 min | 0.34% | B+ |
| October 2025 | 5,611 | 78.5% | 60 min | 0.27% | B+ |
| November 2025 | 5,202 | 80.1% | 76 min | 1.46% | B |
| December 2025 | 5,359 | 74.0% | 75 min | 0.90% | C+ |
| January 2026 (this page) | 4,683 | 83.1% | 74 min | 3.46% | B− |
| February 2026 | 4,484 | 84.9% | 64 min | 1.32% | B |
| March 2026 | 5,400 | 75.3% | 74 min | 2.52% | B |
| April 2026 | 5,156 | 80.8% | 65 min | 0.80% | B+ |
| May 2026 | 5,375 | 77.5% | 74 min | 0.84% | B+ |
| June 2026 | 5,463 | 69.0% | 68 min | 1.17% | C |
Departure window
The best time of day to leave STL in January
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 12 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am818 flights88.4%
- 8am–11am1,201 flights86.3%
- 11am–2pm614 flights83.6%
- 2pm–5pm694 flights81.0%
- 5pm–8pm896 flights78.7%
- 8pm–5am460 flights76.7%
Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 88.4% of the time, against 76.7% for the overnight window. That is 12 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 1,201 flights scheduled in it.
Across the week, Wednesday is the strongest day at 91.1% on time and Saturday the weakest at 71.9%. 19 points is a smaller lever than departure hour, but it is free.
Carrier by carrier
Which airlines ran best at STL in January
The two carriers here are closely matched: half a point separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Southwest Airlines | 2,936 | 83.9% | 52 min | 2.08% | B |
| American Airlines | 366 | 84.5% | 180 min | 8.20% | B− |
| Delta Air Linesthin sample | 352 | 88.2% | 57 min | 3.69% | A− |
| Republic Airwaysthin sample | 301 | 86.2% | 87 min | 8.64% | A− |
| SkyWest Airlinesthin sample | 205 | 71.3% | 95 min | 1.46% | C |
| Envoy Airthin sample | 129 | 76.2% | 68 min | 5.43% | B− |
| PSA Airlinesthin sample | 122 | 81.5% | 187 min | 11.48% | B− |
| United Airlinesthin sample | 117 | 80.5% | 56 min | 3.42% | B− |
| Frontier Airlinesthin sample | 114 | 69.4% | 136 min | 2.63% | C |
| Alaska Airlinesthin sample | 38 | 81.1% | 70 min | 2.63% | B |
American Airlines cancels 8.2% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Route by route
Busiest routes out of STL in January
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| STL to ATL · Atlantathin sample | 279 | 88.1% | 84 min | 6.45% | A− |
| STL to DEN · Denverthin sample | 251 | 83.5% | 60 min | 0.80% | B+ |
| STL to MCO · Orlandothin sample | 215 | 82.1% | 89 min | 0.93% | B+ |
| STL to LGA · New Yorkthin sample | 215 | 86.2% | 70 min | 5.58% | A− |
| STL to PHX · Phoenixthin sample | 199 | 84.5% | 111 min | 2.51% | B |
| STL to DCA · Washingtonthin sample | 199 | 76.2% | 119 min | 8.54% | B− |
| STL to DFW · Dallas-Fort Worththin sample | 169 | 81.6% | 115 min | 10.06% | B− |
| STL to LAS · Las Vegasthin sample | 161 | 78.6% | 42 min | 0.62% | B+ |
| STL to ORD · Chicagothin sample | 156 | 71.1% | 65 min | 4.49% | C− |
| STL to CLT · Charlottethin sample | 155 | 89.4% | 188 min | 8.39% | A− |
| STL to MSP · Minneapolisthin sample | 150 | 82.6% | 105 min | 0.67% | B+ |
| STL to DAL · Dallasthin sample | 145 | 90.5% | 83 min | 5.52% | A− |
| STL to DTW · Detroitthin sample | 122 | 75.4% | 90 min | 0.00% | B+ |
| STL to MDW · Chicagothin sample | 121 | 86.7% | 52 min | 0.83% | A+ |
| STL to MIA · Miamithin sample | 110 | 81.5% | 117 min | 1.82% | B |
| STL to HOU · Houstonthin sample | 107 | 85.0% | 47 min | 0.00% | A+ |
| STL to TPA · Tampathin sample | 102 | 84.2% | 52 min | 0.98% | B+ |
| STL to BOS · Bostonthin sample | 102 | 81.2% | 40 min | 5.88% | B− |
| STL to PHL · Philadelphiathin sample | 102 | 88.7% | 96 min | 4.90% | A− |
| STL to BNA · Nashvillethin sample | 96 | 89.0% | 47 min | 4.17% | A− |
| STL to RSW · Fort Myersthin sample | 92 | 80.0% | 52 min | 1.09% | B |
| STL to EWR · Newarkthin sample | 88 | 88.6% | 79 min | 10.23% | A− |
| STL to FLL · Fort Lauderdalethin sample | 77 | 67.5% | 36 min | 0.00% | C+ |
| STL to LAX · Los Angelesthin sample | 75 | 73.3% | 57 min | 0.00% | C+ |
| STL to BWI · Baltimorethin sample | 74 | 84.3% | 31 min | 5.41% | B− |
Delay causes
What held STL up in January
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 56,000 reported delay minutes.
- 40%Carrier
- 36%Late-arriving aircraft
- 18%National Airspace System
- 6%Extreme weather
36% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 56,000 reported delay minutes here, that single category outweighs weather by 6 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 56,246 reported delay minutes.
Cancellations run at 3.46%, against 4.71% nationally. That is about one flight in 30 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
5.5% of arrivals land an hour or more late, close to the national 7.6%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
What to do with this
Flying from STL in January
For a January trip through STL: this is one of the better months to be flying from here, 83.1% on time with 3.46% cancelled. That is a base rate for the month as a whole; a single storm can still spoil a particular day.
Related
Where to go next
- St. Louis Lambert International (STL), the whole year
- STL in July71.7%
- STL in August79.7%
- STL in September83.8%
- STL in October78.5%
- STL in November80.1%
- STL in December74.0%
- STL in February84.9%
- STL in March75.3%
- STL in April80.8%
- STL in May77.5%
- STL in June69.0%
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.