BTS DATA COMPLETE THROUGH JUNE 2026HISTORICAL ODDS · NOT LIVE FLIGHT STATUS
DelayOddsKnow the route before you book
BOS→DEN

Boston, MA (BOS) to Denver, CO (DEN) flight delay odds

75.3% of 3,899 official scheduled BOS-to-DEN flights arrived on time; 14.4% arrived at least 30 minutes late and 1.2% were cancelled during July 2025–June 2026.

Source: U.S. Bureau of Transportation Statistics · Reporting window: July 2025–June 2026 · Updated September 16, 2026

HISTORICAL ROUTE SIGNALGenerally reliable
75.3%arrived on time
14.4%30+ min late
1.2%cancelled
3,899scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late7.3%all scheduled flights
120+ minutes late2.4%all scheduled flights
Diverted0.3%did not reach as scheduled
Average arrival+4.8 mincompleted flights

Which departure time was most reliable for BOS to DEN?

Among qualifying BOS-to-DEN departure window results, Early morning had the highest on-time rate: 86.6% of 1,170 flights. Evening was lowest at 51.0% across 768 flights.

Departure windowFlightsOn time30+ minCancelled
Early morning1,17086.6%5.7%1.5%
Late morning92985.4%7.6%1.1%
Afternoon1,03271.6%16.8%1.1%
Evening76851.0%32.6%1.0%

Which weekday was most reliable for BOS to DEN?

Among qualifying BOS-to-DEN weekday results, Saturday had the highest on-time rate: 78.8% of 477 flights. Thursday was lowest at 70.8% across 579 flights.

DayFlightsOn time30+ minCancelled
Monday58777.0%13.6%3.2%
Tuesday54378.3%12.3%1.5%
Wednesday54778.4%13.2%0.5%
Thursday57970.8%19.2%0.5%
Friday59072.5%14.9%0.8%
Saturday47778.8%11.7%0.6%
Sunday57672.4%15.1%0.9%

Which airline was most reliable for BOS to DEN?

Among qualifying BOS-to-DEN airline results, United Airlines had the highest on-time rate: 81.9% of 1,908 flights. Southwest Airlines was lowest at 64.0% across 910 flights.

AirlineFlightsOn time30+ minCancelled
United Airlines1,90881.9%11.1%1.0%
Southwest Airlines91064.0%20.5%0.9%
JetBlue Airways68169.5%18.4%1.8%
Delta Air Lines40080.0%9.2%1.8%

Which month was most reliable for BOS to DEN?

Among qualifying BOS-to-DEN month results, November 2025 had the highest on-time rate: 87.4% of 293 flights. July 2025 was lowest at 67.2% across 427 flights.

MonthFlightsOn time30+ minCancelled
July 202542767.2%18.5%1.2%
August 202539777.6%14.6%0.5%
September 202533372.1%20.1%0.3%
October 202534276.9%13.5%0.3%
November 202529387.4%7.5%0.3%
December 202530172.8%16.6%0.7%
January 202625969.9%13.5%3.9%
February 202626673.3%12.4%7.5%
March 202630075.3%14.3%0.7%
April 202628484.5%9.2%0.0%
May 202632380.5%11.1%0.3%
June 202637470.1%17.6%0.3%

What drove BOS to DEN delay minutes?

Late aircraft was the largest recorded BOS-to-DEN delay category, accounting for 44.9% of 52,325 BTS-attributed delay minutes during July 2025–June 2026.

Airline24.5%
Late aircraft44.9%
National airspace27.8%
Weather2.7%
Security0.0%
This is historical evidence, not a forecast.

Weather, schedules and operations change. For a trip you have already booked, use the airline or airport for live status.