Route on-time record
DEN to BOS: most on-time flights and the best time to fly
Denver (Denver International Airport) to Boston (Boston Logan International Airport). 3,911 nonstop flights in Jun 2025 to May 2026, 72% arrived within 15 minutes and 1.2% were cancelled. The most reliable flight number was United 2656 at 11:59 PM.
Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.
DEN → BOS
Denver to Boston: 3,911 nonstop flights a year
On time (12 months)
72%
Cancelled
1.2%
avg delay 21 min
Best time to leave
Before 9 AM
88% on time vs 46% 6 to 9 PM
Most reliable airline
United
76% 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 · United 2656
11:59 PM → 5:51 AM3h 59m nonstop
Local times, typical schedule. Last flown 2026-05-31.
89%
chance on time
- On time (history)
- 93%
- Cancelled
- 2.0%
- Avg arrival delay
- 4 min
- Arrived on time 93% of the time (97 flights, Jun 2025 to May 2026).
- Departs outside DEN's trouble window (2 PM to 8 PM, when 79% of its 174 ground stops and delay programs started).
Moderate track record · 97 flights
Find United 2656 fares Opens this date on Aviasales#2 · United 558
7:45 AM → 1:47 PM4h 02m nonstop
Local times, typical schedule. Last flown 2026-05-31.
88%
chance on time
- On time (history)
- 89%
- Cancelled
- 0.6%
- Avg arrival delay
- 6 min
- Arrived on time 89% of the time (337 flights, Jun 2025 to May 2026).
- Leaves in this route's most on-time window (Before 9 AM: 88% on time; 6 to 9 PM: 46%).
- Departs outside DEN's trouble window (2 PM to 8 PM, when 79% of its 174 ground stops and delay programs started).
- Lands inside BOS's trouble window: 79% of its 196 ground stops and delay programs started between noon and 6 PM.
Strong track record · 337 flights
Find United 558 fares Opens this date on Aviasales#3 · United 1232
9:35 AM → 3:37 PM4h 02m nonstop
Local times, typical schedule. Last flown 2026-05-31.
83%
chance on time
- On time (history)
- 88%
- Cancelled
- 1.4%
- Avg arrival delay
- 9 min
- Arrived on time 88% of the time (142 flights, Jun 2025 to May 2026).
- Departs outside DEN's trouble window (2 PM to 8 PM, when 79% of its 174 ground stops and delay programs started).
- Lands inside BOS's trouble window: 79% of its 196 ground stops and delay programs started between noon and 6 PM.
Moderate track record · 142 flights
Find United 1232 fares Opens this date on Aviasales#4 · Delta 499
11:35 AM → 5:32 PM3h 59m nonstop
Local times, typical schedule. Last flown 2026-05-31.
75%
chance on time
- On time (history)
- 76%
- Cancelled
- 1.4%
- Avg arrival delay
- 17 min
- Arrived on time 76% of the time (343 flights, Jun 2025 to May 2026).
- Departs outside DEN's trouble window (2 PM to 8 PM, when 79% of its 174 ground stops and delay programs started).
- Lands inside BOS's trouble window: 79% of its 196 ground stops and delay programs started between noon and 6 PM.
Strong track record · 343 flights
Find Delta 499 fares Opens this date on Aviasales#5 · JetBlue 994
11:28 PM → 5:47 AM3h 48m nonstop
Local times, typical schedule. Last flown 2026-05-31.
73%
chance on time
- On time (history)
- 72%
- Cancelled
- 1.4%
- Avg arrival delay
- 23 min
- Arrived on time 72% of the time (275 flights, Jun 2025 to May 2026).
- Departs outside DEN's trouble window (2 PM to 8 PM, when 79% of its 174 ground stops and delay programs started).
- 75% of its delay minutes came from the plane arriving late from an earlier flight.
Strong track record · 275 flights
Find JetBlue 994 fares Opens this date on Aviasales#6 · United 779
4:01 PM → 9:59 PM3h 58m nonstop
Local times, typical schedule. Last flown 2026-05-31.
72%
chance on time
- On time (history)
- 74%
- Cancelled
- 0.0%
- Avg arrival delay
- 12 min
- Arrived on time 74% of the time (58 flights, Jun 2025 to May 2026).
- Never cancelled in 58 scheduled flights.
- Departs inside DEN's trouble window: 79% of its 174 ground stops and delay programs started between 2 PM and 8 PM.
- Short track record (58 flights), so its score leans on the airline's record at this hour.
Limited track record · 58 flights
Find United 779 fares Opens this date on Aviasales#7 · United 1356
5:51 PM → 11:59 PM4h 04m nonstop
Local times, typical schedule. Last flown 2026-05-31. Same departure also flew as United 1101; its record covers all of them.
69%
chance on time
- On time (history)
- 73%
- Cancelled
- 2.7%
- Avg arrival delay
- 17 min
- Arrived on time 73% of the time (142 flights, Jun 2025 to May 2026).
- Departs inside DEN's trouble window: 79% of its 174 ground stops and delay programs started between 2 PM and 8 PM.
- 59% of its delay minutes came from the plane arriving late from an earlier flight.
Moderate track record · 142 flights
Find United 1356 fares Opens this date on Aviasales#8 · JetBlue 494
2:20 PM → 8:19 PM3h 59m nonstop
Local times, typical schedule. Last flown 2026-05-31.
68%
chance on time
- On time (history)
- 69%
- Cancelled
- 1.3%
- Avg arrival delay
- 15 min
- Arrived on time 69% of the time (75 flights, Jun 2025 to May 2026).
- Departs inside DEN's trouble window: 79% of its 174 ground stops and delay programs started between 2 PM and 8 PM.
Moderate track record · 75 flights
Find JetBlue 494 fares Opens this date on Aviasales#9 · United 597
2:10 PM → 8:13 PM4h 03m nonstop
Local times, typical schedule. Last flown 2026-05-31.
68%
chance on time
- On time (history)
- 70%
- Cancelled
- 1.5%
- Avg arrival delay
- 24 min
- Arrived on time 70% of the time (267 flights, Jun 2025 to May 2026).
- Departs inside DEN's trouble window: 79% of its 174 ground stops and delay programs started between 2 PM and 8 PM.
Strong track record · 267 flights
Find United 597 fares Opens this date on Aviasales#10 · JetBlue 394
2:35 PM → 8:34 PM3h 55m nonstop
Local times, typical schedule. Last flown 2026-05-20.
67%
chance on time
- On time (history)
- 69%
- Cancelled
- 2.2%
- Avg arrival delay
- 27 min
- Arrived on time 69% of the time (312 flights, Jun 2025 to May 2026).
- Departs inside DEN's trouble window: 79% of its 174 ground stops and delay programs started between 2 PM and 8 PM.
Strong track record · 312 flights
Find JetBlue 394 fares Opens this date on Aviasales
Airlines on this route
Season-adjusted chance of operating and arriving on time.
- United Airlines76%
1,916 flights · 76% on time as flown · 0.9% cancel
- Delta Air Lines74%
415 flights · 76% on time as flown · 1.4% cancel
- JetBlue69%
675 flights · 70% on time as flown · 1.8% cancel
- Southwest Airlines60%
905 flights · 60% on time as flown · 1.1% cancel
On time by departure time
All airlines, scheduled local departure, Jun 2025 to May 2026.
- Before 9 AM88%
458 flights · avg delay 6 min
- 9 AM to noon73%
1,115 flights · avg delay 17 min
- Noon to 3 PM65%
753 flights · avg delay 31 min
- 3 to 6 PM66%
825 flights · avg delay 25 min
- 6 to 9 PM46%
203 flights · avg delay 38 min
- After 9 PM82%
557 flights · avg delay 13 min
Best day: Saturday (76%). Worst: Friday (68%).
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 volume43%
- Late-arriving aircraft36%
- Airline (crew, maintenance, boarding)20%
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
DEN to BOS questions
- What time of day is best to fly DEN to BOS?
- Before 9 AM: 88% of flights arrived on time, against 46% for departures 6 to 9 PM. Later flights inherit delays from earlier ones, so the first departures of the day usually run best.
- Which airline is most on time from DEN to BOS?
- United, with a season-adjusted 76% chance of operating and arriving on time over 1,916 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 DEN to BOS?
- September (62% on time); the best was November (81%), 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 DEN
- BOS to DEN (return)
- DEN to PHX 75%
- DEN to SLC 77%
- DEN to LAX 79%
- DEN to LAS 75%
- DEN to SEA 73%
- DEN to ORD 70%
- DEN to DFW 75%
- DEN to SAN 76%
- DEN to MSP 78%
- DEN to ATL 80%
- DEN to SFO 68%
- DEN to AUS 76%
Live status: FAA delays and ground stops