BOS to ORD flight delays

BOS ORD Boston Logan to Chicago O'Hare · 867 miles

21,098 flights were scheduled from BOS to ORD over July 2023 through June 2026. Of the 20,626 that made the trip, 77.1% reached the gate less than 15 minutes behind schedule. These are arrival figures: “on time” means the flight reached the gate less than 15 minutes behind schedule. Arrivals are what decide whether you make the connection, so route and airline pages are scored on them rather than on pushback.

Data through June 2026 · Bureau of Transportation Statistics

The route in brief

Flights in the window
21,098
Arrived on time
77.1%
Cancelled
1.9%
Scheduled distance
867 miles

Cancellations are counted against everything scheduled. Diverted flights are counted with them rather than as very late arrivals, which is why the on-time share and the cancellation rate do not add up to everything that happened.

Airline by airline

Airlines with at least 100 flights on BOS–ORD, busiest first. Same route, same weather, same air traffic — which makes this the fairest comparison on the site.

Airline Arrived on time Typical delay Cancelled Flights
United Airlines 79.2% 78 min 1.5% 7,310
American Airlines 77.1% 92 min 1.9% 5,181
Delta Air Lines 71.1% 77 min 1.8% 2,797
Republic Airways 78.6% 70 min 3.2% 2,386
JetBlue Airways 73.9% 71 min 1.1% 1,766
Envoy Air 78.9% 88 min 2.3% 1,385
Spirit Airlines 84.5% 6.5% 153
SkyWest Airlines 71.9% 154 min 4.2% 120

A dash under typical delay means fewer than 30 of that airline’s flights arrived 15 minutes late or more — too few to average.

Month by month

July was the month to avoid on BOS–ORD: 67.8% of flights arrived on time, against 82.6% in February. Each bar pools three years of that calendar month.

Share of flights that arrived on time, by calendar month. Best month in green, worst in amber. The hairline sits at the overall rate, 77.1%.
Arrival on-time share, BOS to ORD, by calendar month
Month Share flights that arrived on time Flights
January 78.4% 1,454
February 82.6% 1,405
March 81.6% 1,673
April 78.8% 1,720
May 77% 2,006
June 75.4% 2,073
July 67.8% 1,897
August 73.3% 1,971
September 75.2% 1,834
October 76.4% 1,852
November 81.5% 1,691
December 80.6% 1,522

Both ends of the route

A route’s record is built out of two airports’ habits. The hour-by-hour grid for each is on its own page.

BOS to ORD in one number

BOS → ORD

When a flight on this route was late, it was late by about 81 min.

July 2023–June 2026 · 21,098 flights

77.1% of flights arrived on time

Questions about BOS to ORD

Which airline is most reliable from BOS to ORD?
Spirit Airlines — its flights on this pairing arrived on time 84.5% of the time, with 153 scheduled. Delta Air Lines came in at 71.1% over 2,797 scheduled. Airlines with fewer than 100 flights on the route are not rated.
What is the worst month to fly BOS to ORD?
July, at 67.8% of arrivals on time, with 1,897 flights scheduled. February was the best of the year at 82.6%.
How late are BOS–ORD flights when they are late?
81 min on average, counting only the flights that arrived 15 minutes or more behind schedule. The on-time flights are left out of that average on purpose — mixing them in would flatter it.
How often is the BOS to ORD flight cancelled?
1.9% of scheduled flights on this route were cancelled, July 2023 through June 2026. Diverted flights are counted with the cancellations rather than as late arrivals.
Are these departure or arrival numbers?
Arrival. A flight counts as on time here if it reached the gate at ORD less than 15 minutes behind schedule. Airport pages score departures instead, because that is the number you can act on when you pick a booking time.