Route profile
STL→MIA
Flight reliability, delays and best times to fly from St. Louis to Miami, 1,068 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 70% of comparable major US routes (4,598 compared)
Calculated from 3,109 flights. How this is calculated · What counts as on time
STL → MIA arrives on time 81.3% of the time; the return trip, MIA → STL, arrives on time 72.8% of the time, an 8.5-point gap between the two directions of the same city pair.
STL → MIA spends 22.6 minutes on the ground on a 1,068-mile trip: 13.3 minutes from pushback to wheels-up at STL and 9.4 minutes from touchdown to gate at MIA.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
Which day you fly matters unusually much here, a wider weekday spread than 96% of 4,467 comparable routes.
88.1% on time on a typical Wednesday, against 72.3% on a Saturday.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,467 in the comparison.
What sets this route apart
Where STL to MIA differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
STL to MIA struggles most at 8 AM: 80.0% of its flights scheduled then arrive on time, 5.9 points behind the 85.9% on routes of similar length at the same hour. Against all other routes the gap is 5.9 points.
STL to MIA is at its best against routes of similar length for flights scheduled at 11 AM: 85.1% arrive on time, 5.2 points ahead of the 79.9% those routes manage at that hour.
STL to MIA holds up on Thursdays better than routes of similar length do: 86.7% on time to their 75.8%, a 10.9 points lead. Against all other routes the gap is 9.9 points.
July is kinder to STL to MIA than to routes of similar length: 78.4% on time against 68.1%, 10.3 points better. Against all other routes the gap is 8.7 points.
American Airlines does better on STL to MIA than on its routes of similar length: 86.6% on time here, 74.0% there, 12.6 points apart. Against all other routes the gap is 11.5 points.
STL to MIA against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 8 AM departures | 80.0% | routes of similar length | 85.9% | −5.9 pts | 290 here, 192,328 there |
| Hour: 11 AM departures | 85.1% | routes of similar length | 79.9% | +5.2 pts | 288 here, 186,182 there |
| Weekday: Thursday | 86.7% | routes of similar length | 75.8% | +10.9 pts | 406 here, 424,018 there |
| Month: July | 78.4% | routes of similar length | 68.1% | +10.3 pts | 282 here, 312,940 there |
| Airline: American Airlines | 86.6% | routes of similar length | 74.0% | +12.6 pts | 1,504 here, 585,340 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 1,068 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
When it goes wrong
July 2023 – July 2026
34 min late
against a median of 7 min early
Percentiles over 3,109 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at MIA after arriving from STL.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 35% | Likely to miss |
| 45 min | 18% | High risk |
| 60 min | 11% | Some risk |
| 90 min | 5.4% | Some risk |
| 120 min | 3.1% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.96% of the time and diverts 0.39% of the time, which a late arrival never shows up in.
Chance of missing is the share of 3,067 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 34 minutes late (90th-percentile gate arrival delay), over 3,109 operations.
Any other layover length: connection checker.
Best time to fly
STL → MIA flights departing 5–9 AM arrived on time 87.7% of the time, against 66.3% for 3–6 PM departures, a gap of 21.4 percentage points.
By departure window
By departure hour
- 12 AM to 4 AM: too few flights to score
- 5 AM: 90.4% on time from 1,130 flights
- 6 AM to 7 AM: too few flights to score
- 8 AM: 80.0% on time from 292 flights
- 9 AM: too few flights to score
- 10 AM: 80.0% on time from 134 flights
- 11 AM: 85.1% on time from 291 flights
- 12 PM: 78.0% on time from 261 flights
- 1 PM to 3 PM: too few flights to score
- 4 PM: 70.3% on time from 240 flights
- 5 PM: too few flights to score
- 6 PM: 72.5% on time from 279 flights
- 7 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why STL → MIA runs late
July 2023 – July 2026
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
Share of the delay minutes US DOT attributed to each cause for STL → MIA. Only delays of 15 minutes or more are attributed. What the five causes mean
Late-arriving aircraft is the largest cause on STL → MIA, at 35.9%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 87.7% of the time and 3–6 PM departures 66.3%.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| American Airlines | 1,523 | 86.6% | 1.05% | -10 min | 4.7% |
| Southwest Airlines | 1,273 | 76.0% | 0.86% | -2 min | 6.4% |
| Envoy Air | 303 | 78.5% | 0.99% | -9 min | 6.0% |
American Airlines flew 49.1% of the 3,099 flights listed.
American Airlines arrived on time 10.6 percentage points more often than Southwest Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| AA1716 American Airlines | 5:15 AM | 628 | 90.5% |
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Saturday the least, a gap of 15.8 percentage points.
By month
- Jan: 79.4%
- Feb: 83.6%
- Mar: 75.1%
- Apr: 88.2%
- May: 77.9%
- Jun: 76.8%
- Jul: 78.4%
- Aug: 83.7%
- Sep: 86.1%
- Oct: 86.0%
- Nov: 88.8%
- Dec: 77.5%
March is historically the weakest month and November the strongest, a spread of 13.7 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: too few flights to score (46)
- August 2023: too few flights to score (41)
- September 2023: too few flights to score (39)
- October 2023: too few flights to score (63)
- November 2023: too few flights to score (65)
- December 2023: too few flights to score (83)
- January 2024: too few flights to score (93)
- February 2024: too few flights to score (95)
- March 2024: too few flights to score (107)
- April 2024: too few flights to score (69)
- May 2024: too few flights to score (88)
- June 2024: too few flights to score (68)
- July 2024: too few flights to score (66)
- August 2024: too few flights to score (63)
- September 2024: too few flights to score (60)
- October 2024: too few flights to score (67)
- November 2024: too few flights to score (89)
- December 2024: too few flights to score (93)
- January 2025: too few flights to score (97)
- February 2025: too few flights to score (88)
- March 2025: too few flights to score (106)
- April 2025: too few flights to score (99)
- May 2025: too few flights to score (102)
- June 2025: too few flights to score (78)
- July 2025: too few flights to score (74)
- August 2025: too few flights to score (73)
- September 2025: too few flights to score (68)
- October 2025: too few flights to score (84)
- November 2025: too few flights to score (105)
- December 2025: too few flights to score (99)
- January 2026: too few flights to score (110)
- February 2026: too few flights to score (110)
- March 2026: 80.0% from 136 flights
- April 2026: too few flights to score (96)
- May 2026: too few flights to score (90)
- June 2026: too few flights to score (99)
- July 2026: too few flights to score (100)
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 82.2% against 82.9% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 3,109 STL → MIA flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed