Route on-time record
SDF to BOS: most on-time flights and the best time to fly
Louisville (Louisville Muhammad Ali International Airport) to Boston (Boston Logan International Airport). 707 nonstop flights in Jun 2025 to May 2026, 70% arrived within 15 minutes and 1.8% were cancelled. The most reliable flight number was Republic 5615 at 1:56 PM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
SDF → BOS
Louisville to Boston: 707 nonstop flights a year
On time (12 months)
70%
Cancelled
1.8%
avg delay 23 min
Best time to leave
9 AM to noon
92% on time vs 64% 3 to 6 PM
Most reliable airline
Republic
71% chance on time
Fares open on our travel partner (Aviasales). Pick the flight number you chose here.
Most reliable nonstop flights
Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.
#1 · Republic 5615 · sold as American Eagle, Delta Connection or United Express
1:56 PM → 4:15 PM2h 25m nonstop
Local times, typical schedule. Last flown 2026-05-31.
70%
chance on time
- On time (history)
- 75%
- Cancelled
- 3.7%
- Avg arrival delay
- 11 min
- Arrived on time 75% of the time (130 flights, Jun 2025 to May 2026).
- Cancelled 3.7% of the time (5 of 135).
- Lands inside BOS's trouble window: 79% of its 196 ground stops and delay programs started between noon and 6 PM.
Moderate track record · 130 flights
Find 1:56 PM flight fares Opens this date on Aviasales#2 · Envoy 3850 · sold as American Eagle
12:11 PM → 2:38 PM2h 27m nonstop
Local times, typical schedule. Last flown 2026-05-16.
67%
chance on time
- On time (history)
- 75%
- Cancelled
- 0.0%
- Avg arrival delay
- 10 min
- Arrived on time 75% of the time (12 flights, Jun 2025 to May 2026).
- Lands inside BOS's trouble window: 79% of its 196 ground stops and delay programs started between noon and 6 PM.
- Short track record (12 flights), so its score leans on the airline's record at this hour.
Limited track record · 12 flights
Find 12:11 PM flight fares Opens this date on Aviasales#3 · Envoy 3767 · sold as American Eagle
1:30 PM → 3:51 PM2h 21m nonstop
Local times, typical schedule. Last flown 2026-04-06.
62%
chance on time
- On time (history)
- 69%
- Cancelled
- 0.0%
- Avg arrival delay
- 17 min
- Arrived on time 69% of the time (26 flights, Jun 2025 to May 2026).
- Lands inside BOS's trouble window: 79% of its 196 ground stops and delay programs started between noon and 6 PM.
- Short track record (26 flights), so its score leans on the airline's record at this hour.
Limited track record · 26 flights
Find 1:30 PM flight fares Opens this date on Aviasales#4 · Envoy 4170 · sold as American Eagle
4:35 PM → 7:02 PM2h 27m nonstop
Local times, typical schedule. Last flown 2026-05-20.
60%
chance on time
- On time (history)
- 52%
- Cancelled
- 0.0%
- Avg arrival delay
- 29 min
- Arrived on time 52% of the time (65 flights, Jun 2025 to May 2026).
- Never cancelled in 65 scheduled flights.
- Leaves in this route's least on-time window (3 to 6 PM: 64% on time; 9 AM to noon: 92%).
Moderate track record · 65 flights
Find 4:35 PM flight fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- Republic Airways (sold as American Eagle, Delta Connection or United Express)71%
527 flights · 73% on time as flown · 2.2% cancel
- Envoy Air (sold as American Eagle)64%
178 flights · 61% on time as flown · 1.1% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- 9 AM to noon92%
91 flights · avg delay 3 min
- Noon to 3 PM67%
293 flights · avg delay 21 min
- 3 to 6 PM64%
297 flights · avg delay 32 min
Best day: Saturday (84%). Worst: Sunday (70%).
On time by month
All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.
What delays this route
- Air traffic control and airport volume60%
- Late-arriving aircraft22%
- Airline (crew, maintenance, boarding)13%
- Severe weather6%
Share of delay minutes by the cause airlines report to the US DOT.
Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure
SDF to BOS questions
- What time of day is best to fly SDF to BOS?
- 9 AM to noon: 92% of flights arrived on time, against 64% for departures 3 to 6 PM.
- Which airline is most on time from SDF to BOS?
- Republic, with a season-adjusted 71% chance of operating and arriving on time over 527 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
- What is the worst month for delays on SDF to BOS?
- September (64% on time); the best was December (87%), averaged over Jun 2023 to May 2026.
- Is this a prediction for my flight?
- No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.
More routes from SDF
- BOS to SDF (return)
- SDF to ORD 79%
- SDF to ATL 89%
- SDF to DFW 74%
- SDF to CLT 82%
- SDF to DTW 82%
- SDF to DEN 83%
- SDF to LGA 83%
- SDF to DCA 79%
- SDF to MDW 85%
- SDF to EWR 86%
- SDF to BWI 86%
- SDF to MCO 81%
Live status: FAA delays and ground stops