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

Washington, DC (IAD) to Chicago, IL (ORD) flight delay odds

Historically, 74.4% of scheduled reportable flights on this direction arrived on time in July 2025–June 2026. The sample includes 2,054 flights.

HISTORICAL ROUTE SIGNALGenerally reliable
74.4%arrived on time
15.1%30+ min late
0.8%cancelled
2,054scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late8.1%all scheduled flights
120+ minutes late4.0%all scheduled flights
Diverted0.2%did not reach as scheduled
Average arrival+12.0 mincompleted flights

When is this route most reliable?

The same route can behave differently through the day. These are scheduled departure windows, not actual departure times. Small time windows with fewer than 40 flights are withheld.

Departure windowFlightsOn time30+ minCancelled
Early morning65587.8%5.2%0.5%
Late morning9691.7%6.2%0.0%
Afternoon50876.0%15.6%0.6%
Evening43246.1%31.9%0.9%
Night36377.4%14.6%1.9%

Weekday comparison

Day-of-week results use at least 30 scheduled flights per row. Look for broad patterns, not tiny percentage differences.

DayFlightsOn time30+ minCancelled
Monday29674.7%13.2%1.4%
Tuesday30078.0%13.0%0.7%
Wednesday29073.8%16.9%0.0%
Thursday29171.8%15.5%0.3%
Friday29775.4%14.5%0.7%
Saturday28876.0%14.2%1.4%
Sunday29271.2%18.5%1.4%

Airline comparison

Marketing-carrier results make codeshare flights easier to compare as travelers buy them. Dedicated route-airline reports require at least 160 flights.

AirlineFlightsOn time30+ minCancelled
United Airlines2,05474.4%15.1%0.8%

Monthly trend

Month-by-month results show whether a twelve-month average hides an unusual period.

MonthFlightsOn time30+ minCancelled
July 202518562.7%28.1%1.6%
August 202519674.5%16.3%1.0%
September 202520378.8%10.8%0.0%
October 202517672.7%13.1%0.0%
November 202515176.2%13.9%2.0%
December 202514675.3%11.0%0.0%
January 202612970.5%12.4%3.1%
February 202611275.0%8.9%0.0%
March 202614874.3%16.9%2.7%
April 202618175.7%16.6%0.0%
May 202621776.5%14.3%0.0%
June 202621079.0%15.2%0.5%

What drove reported delay minutes?

BTS cause minutes are reported for qualifying delayed flights. These shares describe recorded delay minutes—not the chance that a particular cause will affect your next flight.

Airline17.5%
Late aircraft18.2%
National airspace57.1%
Weather7.2%
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.