Route reliability record
DTW→STL
Detroit to St. Louis
- Flights
- 1,899
- Period
- September 2025 to August 2026
- Distance
- 440 mi
- Carriers
- 4
This route lands a B, level with the national rate of 77.3%. About one flight in four arrives 15 minutes late or worse, and those flights are late by about an hour on average. That rests on 1,899 DTW to STL flights, of which Delta Air Lines flew 1,104 at 80.4% on time.
Best time to fly DTW to STL: a 5am–8am departure, ideally on a Saturday. Flights in that window arrived on time 91.6% of the time and Saturday flights 84.3%, against 76.6% for the route overall.
The US average over the same twelve months is 77.3%, so there is little to separate this route from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
76.6%
Arrivals under 15 minutes late, of 1,870 completed flights
Avg delay
64 min
Across delayed arrivals only, not all flights
Cancelled
1.11%
National rate is 1.89%
Best carrier
Delta
80.4% on time across 1,104 flights
These figures cover 1,899 flights between September 2025 and August 2026. The median arrival is 8 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Which airline is most reliable on DTW to STL
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 80.4% of the time; Southwest Airlines manages 74.3%. Sample sizes sit next to every figure, because a two-point gap across 611 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| Delta Air Lines | 1,104 | 80.4% | 63 min | 1.27% | B |
| Southwest Airlines | 611 | 74.3% | 55 min | 0.65% | C+ |
| SkyWest Airlinesthin sample | 183 | 61.2% | 87 min | 1.64% | D |
Delta leads Southwest by 6 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Flight by flight
Flights on DTW to STL
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Best ways to make this trip
The most reliable ways to fly Detroit to St. Louis
Every airline on this route, ranked by how often a scheduled flight actually operated and arrived on time, with its best departure time and most punctual flight number. No nearby airport pair beat these.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. DTW → STLDetroit to St. Louis | Delta Air Lines | 79.4% | 80.4% | 1.27% | 8am–11am, Sat | DL 2822 15:50 |
| 2. DTW → STLDetroit to St. Louis | Southwest Airlines | 73.8% | 74.3% | 0.65% | 8am–11am, Sat | — |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 28 points, against 6 points between the best and worst carrier.
- 5am–8am242 flights91.6%
- 8am–11am431 flights81.0%
- 11am–2pm259 flights79.8%
- 2pm–5pm338 flights76.1%
- 5pm–8pm169 flights73.8%
- 8pm–5am460 flights64.0%
Scale runs 55% to 95%.
The 8pm–5am window is where this operation falls apart: 64.0% on time, against 91.6% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8pm–5am window is the busiest, with 460 flights scheduled in it.
Explore
Filter DTW to STL by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On DTW to STL, the best departure window is 5am–8am at 91.6% on time and the worst is 8pm–5am at 64.0%, a wide gap of 27.6 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am91.6%
- 8–11am81.0%
- 11am–2pm79.8%
- 2–5pm76.1%
- 5–8pm73.8%
- 8pm–5am64.0%
best all US flightsScale 55% to 95%.
Across the year
When delays peak on this route
This route's year swings by 31 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
December is the weak month at 60.5% on time, against 91.9% in September. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. August was the busiest month here, with 180 flights.
Across the week, Saturday is the strongest day at 84.3% on time and Sunday the weakest at 70.5%, a spread of 14 points.
Delay causes
Why this route gets delayed
Carrier accounts for 48% of the 28,000 delay minutes carriers reported here, and the remaining four split what is left.
- 48%Carrier
- 35%Late-arriving aircraft
- 12%National Airspace System
- 6%Extreme weather
- 0%Security
35% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 28,000 reported delay minutes here, that single category outweighs weather by 6 to one. The split is drawn from 28,008 reported delay minutes.
The largest share of delay minutes, 48%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 13,000 of the 28,000 delay minutes reported here.
Cancellations sit at 1.11% against a national 1.89%, which is ordinary. Diversions add another 0.42%.
Connections and stage length
What a delay here actually costs
7.5% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.
At 440 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 81.1% on time across 1,899 flights, 5 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 5 points of difference.
The sample behind these figures is 1,899 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
Work out the risk of missing a connection in STL after this flight
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 91.9% on time and December 60.5%, a swing of 31 points. If the dates move at all, move them out of December before you think about anything else. 1,870 completed flights over 12 months sit behind that.
Common questions
DTW to STL questions
How often is DTW to STL delayed?
About one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 23.4% of the 1,899 flights in this analysis, against 22.7% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on DTW to STL?
Delta Air Lines leads at 80.4% on time across 1,104 flights. Southwest Airlines is at the other end on 74.3%, a gap of 6 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on DTW to STL?
The 5am–8am departure window is the strongest at 91.6% on time. The 8pm–5am window is the weakest at 64.0%, 28 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are December delays on DTW to STL?
December is the weakest month at 60.5% on time, compared with 91.9% in September. Across the year that is 31 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- STL to DTW — the return legseparate record
- Detroit Metropolitan Wayne County (DTW) delay statistics
- St. Louis Lambert International (STL) delay statistics
- Delta Air Lines on DTW to STL80.4%
- Southwest Airlines on DTW to STL74.3%
- SkyWest Airlines on DTW to STL61.2%
- DTW to ORD, a related route72.2%
- DEN to STL, a related route77.7%
- DTW to ATL, a related route78.9%
- Spirit Airlines on-time record100.0%
- Delta Air Lines on-time record80.4%
- Southwest Airlines on-time record74.3%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Direction matters. DTW to STL and STL to DTW are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed DTW to STL’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.