ON TIMEBOARD

STL → RDU on time

St. Louis Lambert (St. Louis, MO) to Raleigh-Durham (Raleigh/Durham, NC). Every scheduled flight, September 2025 to August 2026.

On time
79%
arrived < 15 min late
Cancelled
0.1%
664 flights
Typical arrival
−4 min
median vs schedule
When late
+54 min
average delay
Flights / day
2
1 airline

79% of flights from St. Louis to Raleigh arrived on time over the past 12 months. That is about the typical U.S. route. The 8 a.m. departures ran on time 93% of the time; the 7 p.m. ones 66%. 6% 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 STL → RDU: when a flight was late, it was under 45 minutes late 63% of the time. About 1 in 18 flights landed an hour or more late, and 1 in 221 three hours or more; 0.2% were cancelled outright.

Share of all 664 scheduled flights, past 12 months, by arrival time against schedule.

By airline

AirlineFlightsOn timeCancelledTypical arrival1h+ lateAvg when lateOperated by
Southwest Airlines66479%0.1%−4 min5.6%+54 minSouthwest Airlines

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 STL). Delays build through the day as late planes knock on, so early flights usually do best.

40%70%100%7 a.m. departures: too few flights (39 flights)7a8 a.m. departures: 93% on time (115 flights)938a9 a.m. departures: too few flights (35 flights)9a10 a.m. departures: 91% on time (141 flights)9110a11 a.m. departures: too few flights (1 flights)11anoon departures: too few flights (12 flights)12p1 p.m. departures: too few flights (8 flights)1p2 p.m. departures: too few flights (1 flights)2p3 p.m. departures: too few flights3p4 p.m. departures: too few flights (17 flights)4p5 p.m. departures: too few flights (9 flights)5p6 p.m. departures: too few flights (84 flights)6p7 p.m. departures: 66% on time (127 flights)667p8 p.m. departures: too few flights (75 flights)8p
STL → RDU, 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 STL → RDU, each airline's last flight of the day was cancelled 0.0% of the time, against 0.0% for its earlier flights, about the same. It arrived 3+ hours late 0.3% of the time (earlier flights: 0.7%). 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
Southwest Airlines7:10 p.m.0.0%0.3%0.0%first flight 10:10 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.

By month

Each calendar month pooled over 2023–2026. Best: September (88%). Worst: July (71%).

40%70%100%Jan: 79% on time (101 flights)79JanFeb: too few flights (99 flights)FebMar: 84% on time (165 flights)84MarApr: 85% on time (175 flights)85AprMay: 86% on time (179 flights)86MayJun: 76% on time (175 flights)76JunJul: 71% on time (181 flights)71JulAug: 80% on time (174 flights)80AugSep: 88% on time (160 flights)88SepOct: 85% on time (174 flights)85OctNov: 86% on time (152 flights)86NovDec: 82% on time (159 flights)82Dec

By day of week

DayFlightsOn timeCancelled
Monday99——
Tuesday95——
Wednesday95——
Thursday97——
Friday10082%0.0%
Saturday77——
Sunday10167%1.0%

Why flights were late

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

Late inbound plane 68%Airline (crew, maintenance, ops) 24%Air traffic & airport (NAS) 4%Severe weather 3%

Cancellations: weather 1

Month by month

Not enough months with data to draw a trend.

Worst days in the past year

DateFlightsOn timeCancelled
Nov 30, 202530%0
Apr 26, 2026367%0
Apr 12, 2026367%0
May 31, 20263100%0
May 3, 20263100%0

Questions

How often are flights from STL to RDU on time?

79% of 664 scheduled flights from St. Louis, MO to Raleigh/Durham, NC arrived within 15 minutes of schedule between September 2025 and August 2026. 0.1% were cancelled.

What is the best time of day to fly STL to RDU?

Flights scheduled to leave at 8 a.m. were the most reliable (93% on time). The 7 p.m. departures were the least (66%).

What month has the most delays from STL to RDU?

July (71% on time). The best month is September (88%), over 2023–2026.

Is the last flight of the day from STL to RDU more likely to be cancelled?

Not much. Each airline's last STL–RDU flight of the day was cancelled 0.0% of the time over the past year, against 0.0% 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.