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

Boston, MA (BOS) to Washington, DC (IAD) flight delay odds

81.2% of 1,464 official scheduled BOS-to-IAD flights arrived on time; 11.8% arrived at least 30 minutes late and 2.0% 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
81.2%arrived on time
11.8%30+ min late
2.0%cancelled
1,464scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late6.8%all scheduled flights
120+ minutes late3.1%all scheduled flights
Diverted0.1%did not reach as scheduled
Average arrival+5.4 mincompleted flights

Which departure time was most reliable for BOS to IAD?

Among qualifying BOS-to-IAD departure window results, Early morning had the highest on-time rate: 94.8% of 346 flights. Evening was lowest at 67.4% across 356 flights.

Departure windowFlightsOn time30+ minCancelled
Early morning34694.8%1.7%2.0%
Late morning36589.3%5.8%1.9%
Afternoon39774.3%15.9%2.0%
Evening35667.4%23.3%2.2%

Which weekday was most reliable for BOS to IAD?

Among qualifying BOS-to-IAD weekday results, Saturday had the highest on-time rate: 86.9% of 206 flights. Thursday was lowest at 75.4% across 211 flights.

DayFlightsOn time30+ minCancelled
Monday21280.7%9.9%5.2%
Tuesday20783.6%10.1%1.9%
Wednesday20481.4%12.3%1.0%
Thursday21175.4%13.7%2.4%
Friday21384.0%11.7%0.5%
Saturday20686.9%8.3%0.5%
Sunday21176.8%16.6%2.8%

Which airline was most reliable for BOS to IAD?

Only United Airlines met the BOS-to-IAD airline threshold: 81.3% of 1,461 scheduled flights arrived on time during July 2025–June 2026.

AirlineFlightsOn time30+ minCancelled
United Airlines1,46181.3%11.7%2.1%
Republic Airways333.3%66.7%0.0%

Which month was most reliable for BOS to IAD?

Among qualifying BOS-to-IAD month results, May 2026 had the highest on-time rate: 87.9% of 124 flights. July 2025 was lowest at 70.2% across 124 flights.

MonthFlightsOn time30+ minCancelled
July 202512470.2%23.4%1.6%
August 202513379.7%15.8%0.0%
September 202514380.4%11.2%1.4%
October 202512472.6%16.9%0.8%
November 202511985.7%9.2%1.7%
December 202512283.6%14.8%0.0%
January 202611278.6%8.0%8.0%
February 202610481.7%5.8%7.7%
March 202611985.7%9.2%2.5%
April 202612087.5%10.0%0.0%
May 202612487.9%5.6%0.8%
June 202612081.7%10.0%1.7%

What drove BOS to IAD delay minutes?

Late aircraft was the largest recorded BOS-to-IAD delay category, accounting for 48.2% of 18,428 BTS-attributed delay minutes during July 2025–June 2026.

Airline17.7%
Late aircraft48.2%
National airspace32.1%
Weather2.0%
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.