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

Chicago, IL (MDW) to Portland, OR (PDX) flight delay odds

Historically, 61.1% of scheduled reportable flights on this direction arrived on time in July 2025–June 2026. The sample includes 686 flights.

HISTORICAL ROUTE SIGNALVariable
61.1%arrived on time
21.4%30+ min late
0.7%cancelled
686scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late10.2%all scheduled flights
120+ minutes late3.8%all scheduled flights
Diverted0.1%did not reach as scheduled
Average arrival+18.1 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 morning12073.3%10.8%0.0%
Late morning13672.1%14.0%0.7%
Afternoon16261.7%14.8%0.6%
Evening12055.8%31.7%0.0%
Night14844.6%35.8%2.0%

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
Monday10361.2%24.3%0.0%
Tuesday10662.3%21.7%0.0%
Wednesday10365.0%16.5%0.0%
Thursday10458.7%20.2%1.9%
Friday10252.0%23.5%1.0%
Saturday8770.1%14.9%1.1%
Sunday8159.3%29.6%1.2%

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
Southwest Airlines68661.1%21.4%0.7%

Monthly trend

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

MonthFlightsOn time30+ minCancelled
July 20258861.4%26.1%0.0%
August 20258464.3%15.5%0.0%
September 20258281.7%8.5%0.0%
October 20255477.8%7.4%0.0%
November 20253066.7%13.3%3.3%
December 20253129.0%29.0%0.0%
January 20263177.4%9.7%0.0%
February 20262860.7%17.9%0.0%
March 20265836.2%46.6%3.4%
April 20266058.3%21.7%1.7%
May 20266163.9%19.7%1.6%
June 20267946.8%34.2%0.0%

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.

Airline33.6%
Late aircraft39.7%
National airspace20.3%
Weather5.7%
Security0.7%
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.