Route profile
STL→DTW
Flight reliability, delays and best times to fly from St. Louis to Detroit, 440 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 76% of comparable major US routes (4,598 compared)
Calculated from 5,777 flights. How this is calculated · What counts as on time
STL → DTW arrives on time 84.4% of the time; the return trip, DTW → STL, arrives on time 82.0% of the time, a 2.3-point gap between the two directions of the same city pair.
STL → DTW spends 21.0 minutes on the ground on a 440-mile trip: 11.9 minutes from pushback to wheels-up at STL and 9.0 minutes from touchdown to gate at DTW.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What sets this route apart
Where STL to DTW differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
STL to DTW is at its best against routes of similar length for flights scheduled at 12 PM: 93.4% arrive on time, 12.3 points ahead of the 81.1% those routes manage at that hour. Against all other routes the gap is 14 points.
STL to DTW struggles most at 8 PM: 56.9% of its flights scheduled then arrive on time, 10.8 points behind the 67.7% on routes of similar length at the same hour. Against all other routes the gap is 10.5 points.
STL to DTW holds up on Thursdays better than routes of similar length do: 84.9% on time to their 77.0%, a 7.9 points lead. Against all other routes the gap is 8.1 points.
May is kinder to STL to DTW than to routes of similar length: 87.8% on time against 75.9%, 11.9 points better. Against all other routes the gap is 12.6 points.
Delta Air Lines does better on STL to DTW than on its routes of similar length: 88.3% on time here, 81.4% there, 6.9 points apart. Against all other routes the gap is 6.8 points.
STL to DTW against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 12 PM departures | 93.4% | routes of similar length | 81.1% | +12.3 pts | 136 here, 88,485 there |
| Hour: 8 PM departures | 56.9% | routes of similar length | 67.7% | −10.8 pts | 144 here, 73,870 there |
| Weekday: Thursday | 84.9% | routes of similar length | 77.0% | +7.9 pts | 857 here, 223,392 there |
| Month: May | 87.8% | routes of similar length | 75.9% | +11.9 pts | 484 here, 125,666 there |
| Airline: Delta Air Lines | 88.3% | routes of similar length | 81.4% | +6.9 pts | 3,583 here, 238,233 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 440 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
31 min late
against a median of 10 min early
Percentiles over 5,777 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at DTW after arriving from STL.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 28% | High risk |
| 45 min | 15% | High risk |
| 60 min | 10% | Some risk |
| 90 min | 6.0% | Some risk |
| 120 min | 4.2% | 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 0.76% of the time and diverts 0.07% of the time, which a late arrival never shows up in.
Chance of missing is the share of 5,729 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 31 minutes late (90th-percentile gate arrival delay), over 5,777 operations.
Any other layover length: connection checker.
Best time to fly
STL → DTW flights departing 5–9 AM arrived on time 92.0% of the time, against 72.1% for 6–9 PM departures, a gap of 19.9 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 91.6% on time from 1,126 flights
- 7 AM: too few flights to score
- 8 AM: 93.2% on time from 412 flights
- 9 AM: 85.8% on time from 120 flights
- 10 AM: 87.5% on time from 760 flights
- 11 AM: 88.2% on time from 410 flights
- 12 PM: 93.4% on time from 140 flights
- 1 PM: 81.2% on time from 167 flights
- 2 PM: 85.9% on time from 562 flights
- 3 PM to 4 PM: too few flights to score
- 5 PM: 80.3% on time from 652 flights
- 6 PM: 79.6% on time from 765 flights
- 7 PM: 57.9% on time from 245 flights
- 8 PM: 56.9% on time from 145 flights
- 9 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why STL → DTW runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
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 STL → DTW. Only delays of 15 minutes or more are attributed. What the five causes mean
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 |
|---|---|---|---|---|---|
| Delta Air Lines | 3,622 | 88.3% | 0.97% | -14 min | 5.4% |
| Southwest Airlines | 1,761 | 77.3% | 0.28% | -2 min | 6.5% |
| SkyWest Airlines | 236 | 76.0% | 1.27% | -6 min | 11.6% |
Delta Air Lines flew 64.5% of the 5,619 flights listed.
Delta Air Lines arrived on time 12.3 percentage points more often than SkyWest 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 |
|---|---|---|---|
| DL1626 Delta Air Lines | 6:30 AM | 749 | 91.5% |
Weekly and seasonal patterns
By day of week
Saturday is historically the most reliable day and Monday the least, a gap of 5.1 percentage points.
By month
- Jan: 79.3%
- Feb: 84.4%
- Mar: 84.4%
- Apr: 87.0%
- May: 87.8%
- Jun: 78.7%
- Jul: 74.6%
- Aug: 85.4%
- Sep: 90.5%
- Oct: 88.9%
- Nov: 90.0%
- Dec: 84.9%
July is historically the weakest month and September the strongest, a spread of 15.9 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 77.4% from 166 flights
- August 2023: 85.0% from 176 flights
- September 2023: 84.3% from 166 flights
- October 2023: 85.1% from 175 flights
- November 2023: 92.0% from 163 flights
- December 2023: 88.6% from 158 flights
- January 2024: 78.7% from 128 flights
- February 2024: too few flights to score (108)
- March 2024: 87.5% from 160 flights
- April 2024: 87.4% from 159 flights
- May 2024: 89.3% from 159 flights
- June 2024: 83.6% from 171 flights
- July 2024: 75.1% from 176 flights
- August 2024: 85.5% from 166 flights
- September 2024: 93.7% from 158 flights
- October 2024: 94.7% from 171 flights
- November 2024: 90.9% from 154 flights
- December 2024: 87.7% from 155 flights
- January 2025: 83.9% from 127 flights
- February 2025: too few flights to score (114)
- March 2025: 88.0% from 125 flights
- April 2025: 87.3% from 135 flights
- May 2025: 92.6% from 149 flights
- June 2025: 80.5% from 176 flights
- July 2025: 75.8% from 188 flights
- August 2025: 85.7% from 175 flights
- September 2025: 93.9% from 148 flights
- October 2025: 87.1% from 171 flights
- November 2025: 86.8% from 153 flights
- December 2025: 78.1% from 156 flights
- January 2026: 75.4% from 122 flights
- February 2026: too few flights to score (112)
- March 2026: 78.2% from 161 flights
- April 2026: 86.2% from 167 flights
- May 2026: 82.4% from 179 flights
- June 2026: 71.9% from 173 flights
- July 2026: 70.3% from 177 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 81.3% against 87.2% in the 12 months before — declining by 5.9 percentage points.
Data and methodology
Calculated by FlyerIntel from 5,777 STL → DTW 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