BOS to STL flight delays & on-time performance
Nonstop flights from Boston Logan International Airport to St. Louis Lambert International Airport · 1,047 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at BOS or STL right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Boston (BOS) to St. Louis (STL) arrived on time 76% of the time in Aug 2025 – Jul 2026, worse than the 78% national average.
- 1.6% were cancelled, and 8% arrived an hour or more late.
- Envoy Air was the most punctual airline here (82% on time); Southwest Airlines was the least (73%).
- Departures scheduled around 5am did best (97% on time); around 6pm did worst (41%).
- Saturday was the most reliable day to fly (82% on time) and Sunday the least (69%).
- The largest source of delay minutes was late-arriving aircraft (61%).
Which airline is most on time from BOS to STL?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| Envoy AirRegional airline operating American Eagle flights. | 82% | 1.0% | 14 min | 9.0% | 384 |
| Republic AirwaysRegional airline operating flights for American Eagle, Delta Connection and United Express. | 79% | 4.1% | 12 min | 6.5% | 293 |
| Southwest Airlines | 73% | 1.0% | 18 min | 8.4% | 935 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am97%154 flights
- 6am91%172 flights
- 7am93%268 flights
- 8am87%53 flights
- 9am79%66 flights
- 10am90%30 flights
- 11am89%82 flights
- 12pm76%97 flights
- 1pm69%59 flights
- 2pm64%72 flights
- 3pm72%123 flights
- 4pm64%78 flights
- 5pm55%138 flights
- 6pm41%149 flights
- 7pm54%71 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday75%3.3% cancelled
- Tuesday79%2.2% cancelled
- Wednesday80%0.9% cancelled
- Thursday72%1.3% cancelled
- Friday78%0.0% cancelled
- Saturday82%0.6% cancelled
- Sunday69%2.5% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Late-arriving aircraft61%
- Airline (crew, maintenance, cleaning, fueling)24%
- Air traffic control & airport congestion12%
- Extreme weather3%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Extreme weather72%
- Air traffic control & airport congestion24%
- Airline (crew, maintenance, cleaning, fueling)4%
- Security0%
BOS to STL: common questions
- How often are BOS to STL flights on time?
- 76% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Boston to St. Louis cancelled?
- 1.6% of scheduled flights were cancelled (25 of 1,612).
- How long are typical delays?
- Across all flights the average arrival delay was 16 min (early arrivals count as zero). Flights that were late arrived 62 min behind schedule on average, and 8.2% of flights were an hour or more late.
- How long is taxi time at BOS?
- Flights on this route spent 19 min taxiing from the gate to takeoff on average.
Related routes
Return trip: STL to BOS — 70% on time
More flights from Boston
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: BOS → STL, nonstop flights by US airlines that report to the DOT. How we calculate this.