ON TIMEBOARD

DTW → SAT on time

Detroit Metro (Detroit, MI) to San Antonio (San Antonio, TX). Every scheduled flight, September 2025 to August 2026.

On time
80%
arrived < 15 min late
Cancelled
0.8%
934 flights
Typical arrival
−10 min
median vs schedule
When late
+56 min
average delay
Flights / day
3
1 airline

80% of flights from Detroit to San Antonio arrived on time over the past 12 months. That is about the typical U.S. route. The 8 a.m. departures ran on time 87% of the time; the 8 p.m. ones 69%. 7% of flights arrived more than an hour late or not at all.

How late?

The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for DTW → SAT: when a flight was late, it was under 45 minutes late 59% of the time. About 1 in 17 flights landed an hour or more late, and 1 in 187 three hours or more; 0.7% were cancelled outright.

Share of all 934 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
Delta Air Lines93480%0.8%−10 min5.8%+56 minDelta Air Lines

Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.

Best time of day to fly

On-time rate by scheduled departure hour (local time at DTW). Delays build through the day as late planes knock on, so early flights usually do best.

40%70%100%8 a.m. departures: 87% on time (311 flights)878a9 a.m. departures: too few flights9a10 a.m. departures: too few flights (28 flights)10a11 a.m. departures: too few flights (9 flights)11anoon departures: too few flights (25 flights)12p1 p.m. departures: 84% on time (200 flights)841p2 p.m. departures: too few flights (1 flights)2p3 p.m. departures: too few flights3p4 p.m. departures: too few flights (5 flights)4p5 p.m. departures: too few flights5p6 p.m. departures: too few flights6p7 p.m. departures: too few flights7p8 p.m. departures: 69% on time (320 flights)698p9 p.m. departures: too few flights (35 flights)9p
DTW → SAT, share of flights arriving on time, by departure hour. Hours with under 100 flights are greyed out.
82%+ on time76–82%68–76%under 68%too few flights

Last flight of the day

On DTW → SAT, each airline's last flight of the day was cancelled 1.4% of the time, against 0.4% for its earlier flights (3.9× as often). It arrived 3+ hours late 0.8% of the time (earlier flights: 0.4%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.

AirlineLast departureLast: cancelledLast: 3h+ lateEarlier: cancelledNext morning
Delta Air Lines8:15 p.m.1.4%0.8%0.4%first flight 8:25 a.m.

Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.

If you need to be in SAT tonight, book an earlier flight so there's a backup if it's cancelled.

By month

Each calendar month pooled over 2023–2026. Best: October (88%). Worst: January (70%).

40%70%100%Jan: 70% on time (188 flights)70JanFeb: 85% on time (170 flights)85FebMar: 83% on time (186 flights)83MarApr: 83% on time (224 flights)83AprMay: 70% on time (260 flights)70MayJun: 80% on time (258 flights)80JunJul: 70% on time (262 flights)70JulAug: 86% on time (263 flights)86AugSep: 82% on time (244 flights)82SepOct: 88% on time (253 flights)88OctNov: 86% on time (230 flights)86NovDec: 80% on time (255 flights)80Dec

By day of week

DayFlightsOn timeCancelled
Monday14279%1.4%
Tuesday14086%0.7%
Wednesday13880%0.0%
Thursday13679%0.7%
Friday13676%0.0%
Saturday10578%0.9%
Sunday13777%1.5%

Why flights were late

Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.

Airline (crew, maintenance, ops) 57%Air traffic & airport (NAS) 23%Late inbound plane 17%Severe weather 3%

Cancellations: airline 6 · weather 1

Month by month

Not enough months with data to draw a trend.

Flight numbers on this route

Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.

FlightDepartsFlightsOn timeCancelledTypical arrivalOperated by
DL 7888:25 a.m.32787%0.6%−14 minDelta Air Lines
DL 24581:38 p.m.13181%0.0%−10 minDelta Air Lines
DL 13658:30 p.m.35969%1.4%−4 minDelta Air Lines

Worst days in the past year

DateFlightsOn timeCancelled
Nov 9, 202530%0
Dec 7, 202530%0
Dec 29, 202530%0
Dec 4, 202530%0
Dec 5, 202530%0

Questions

How often are flights from DTW to SAT on time?

80% of 934 scheduled flights from Detroit, MI to San Antonio, TX arrived within 15 minutes of schedule between September 2025 and August 2026. 0.8% were cancelled.

What is the best time of day to fly DTW to SAT?

Flights scheduled to leave at 8 a.m. were the most reliable (87% on time). The 8 p.m. departures were the least (69%).

What month has the most delays from DTW to SAT?

January (70% on time). The best month is October (88%), over 2023–2026.

Is the last flight of the day from DTW to SAT more likely to be cancelled?

Yes. Each airline's last DTW–SAT flight of the day was cancelled 1.4% of the time over the past year, against 0.4% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.

Related

Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.