Best Time to Fly BOS to ORD: On-Time Stats by Hour & Airline
Logan International → Chicago O'Hare International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 73.0% of Boston (BOS) to Chicago (ORD) flights arrived on time (7,750 scheduled flights). That is 4.6 points below the national average of 77.6%.
Among 6 airlines, Envoy Air led with 77.1% on time and Delta Air Lines was last with 65.8%.
Over 24 months, Tuesday was the most reliable day (80% on time) and July the worst month (71%).
The cancellation rate was 3.0% (US average 1.8%).
BOS to ORD on-time performance by airline
Last 12 months. Airlines with fewer than 30 completed flights are marked “limited data”.
| Airline | On time | Avg delay when late | Cancelled | Flights |
|---|---|---|---|---|
| Envoy Air | 77.1% | 101 min | 3.4% | 442 |
| United Airlines | 75.8% | 85 min | 2.0% | 2,733 |
| American Airlines | 73.4% | 95 min | 3.0% | 2,155 |
| Republic Airways | 71.1% | 81 min | 6.0% | 906 |
| JetBlue | 70.3% | 73 min | 2.8% | 544 |
| Delta Air Lines | 65.8% | 75 min | 3.4% | 970 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly BOS to ORD
On-time arrival % by scheduled departure hour (local time), 14,844 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 5am–6am | 89.8% | 1.3% | 449 |
| 6am–7am | 92.6% | 1.8% | 1,426 |
| 7am–8am | 83.8% | 2.2% | 1,461 |
| 8am–9am | 90.2% | 0.8% | 880 |
| 9am–10am | 86.1% | 1.3% | 788 |
| 10am–11am | 85.1% | 1.4% | 778 |
| 11am–12pm | 80.2% | 1.3% | 971 |
| 12pm–1pm | 83.0% | 1.6% | 1,355 |
| 1pm–2pm | 77.3% | 1.3% | 540 |
| 2pm–3pm | 79.7% | 1.7% | 463 |
| 3pm–4pm | 68.5% | 1.9% | 1,275 |
| 4pm–5pm | 59.8% | 3.1% | 1,273 |
| 5pm–6pm | 56.7% | 3.4% | 1,037 |
| 6pm–7pm | 56.7% | 2.5% | 744 |
| 7pm–8pm | 55.0% | 3.7% | 766 |
| 8pm–9pm | 58.5% | 4.0% | 618 |
| 9pm–10pm | Limited data | 19 | |
| 10pm–11pm | Limited data | 1 | |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on BOS to ORD
On-time arrivals during holiday periods compared with all other days, last 24 months.
| Period | On time | vs other days | Cancelled | Flights |
|---|---|---|---|---|
| Thanksgiving week (Tue before to Mon after) | 69.3% | -7.5 pts | 3.5% | 287 |
| Christmas & New Year (Dec 20 - Jan 3) | 78.7% | +1.8 pts | 0.4% | 452 |
| Summer peak (Jun 15 - Aug 15) | 71.3% | -5.6 pts | 2.8% | 2,900 |
| All other days | 76.8% | — | 1.9% | 11,205 |
Monthly on-time trend
On-time arrival % each month, with the 12-month US average for reference.
What causes delays on this route
Share of reported delay minutes, last 12 months (BTS cause categories).