ORD to BOS flight delays
Chicago, IL (ORD) Boston, MA (BOS) · 867 miles
751 flights · February 2026 – July 2026 · US Bureau of Transportation Statistics
68.26%
Arrived on time
Within 15 minutes of schedule
2.66%
Cancelled
Share of scheduled flights
82 min
When late, late by
Average across delayed arrivals
27 min
Delay per flight
Averaged over every flight flown
What the record says about this route
Which airline you fly changes the odds here. United Airlines arrived on time 13.8 points more often than American Airlines over the same period on the same route — same airports, same weather, same air traffic control. A gap that survives all of that is about how the two airlines are run.
Cancellation, not delay, is the risk worth pricing here: 2.66% of scheduled flights never operated. A late flight still gets you there. A cancelled one leaves you rebooking, and on a route with few daily departures that can mean losing a day.
The two directions do not behave alike. BOS to ORD arrives on time 8.6 points more often than the outbound. Delay accumulates through the flying day, so whichever direction is scheduled later tends to carry the worse record — which is an argument for booking the morning departure if the choice exists.
Flights from Chicago to Boston run late more often than the average route, though not severely.
Which airline should you fly on this route?
Over February 2026 – July 2026, United Airlines arrived on time most often on ORD to BOS. American Airlines was late most often.
Every airline on ORD to BOS
Ranked by how many flights each one operated. A carrier with fewer than 100 flights in the period is listed but not graded.
| Airline | Flights | On time | Cancelled | Avg delay | Grade |
|---|---|---|---|---|---|
| United Airlines | 290 | 73.08% | 1.38% | 74 min | C |
| American Airlines | 239 | 59.31% | 3.35% | 88 min | F |
| Delta Air Lines | 108 | 68.63% | 5.56% | 86 min | F |
| JetBlue Airways | 48 | 74.47% | 2.08% | 86 min | — |
| Republic Airways | 36 | 54.29% | 2.78% | 74 min | — |
| Envoy Air | 30 | 96.67% | 0% | 17 min | — |
The return leg
BOS to ORD Boston back to Chicago 76.83% on time COther routes from Chicago
What these figures do and do not tell you
Everything on this page is counted from the flights that actually operated on ORD to BOS during February 2026 – July 2026, as reported by the airlines to the US Bureau of Transportation Statistics. "On time" is the federal definition: arriving at the gate within 15 minutes of the scheduled time.
A route's record is a description of the past, not a forecast. Weather, air traffic control and the aircraft's earlier flights that day drive most delays, and none of them are predictable from a historical rate. What the record does tell you is whether this route runs late more often than others, and which carrier on it has the better history — which is the part you can actually act on when you book.
Cancellations are counted separately from delays because they are a different problem for a traveller: a late flight still gets you there. How the grade is calculated →