Best Time to Fly ORD to SJU: On-Time Stats by Hour & Airline
Chicago O'Hare International → Luis Munoz Marin International
Data through July 2026 · Last updated October 18, 2026
Over the last 12 months, 73.7% of Chicago (ORD) to San Juan (SJU) flights arrived on time (1,398 scheduled flights). That is 3.9 points below the national average of 77.6%.
United Airlines was the most punctual of the 4 airlines on the route at 79.0%, while Frontier Airlines trailed at 60.5%.
February has been the best month (88% on time) and Sunday the weakest day of the week (73%).
2.3% of flights were cancelled, versus 1.8% nationally.
ORD to SJU 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 |
|---|---|---|---|---|
| United Airlines | 79.0% | 48 min | 0.3% | 665 |
| American Airlines | 72.6% | 63 min | 1.6% | 429 |
| Spirit Airlines | 63.2% | 76 min | 7.6% | 263 |
| Frontier Airlines | 60.5% | 221 min | 7.3% | 41 |
80%+ good 70–79.9% fair <70% poor
Best time of day to fly ORD to SJU
On-time arrival % by scheduled departure hour (local time), 2,671 flights over 24 months.
Show the numbers
| Departure hour | On time | Cancelled | Flights |
|---|---|---|---|
| 12am–1am | 60.5% | 7.3% | 41 |
| 5am–6am | 67.7% | 11.4% | 35 |
| 6am–7am | Limited data | 11 | |
| 7am–8am | Limited data | 16 | |
| 8am–9am | 80.3% | 0.4% | 1,187 |
| 9am–10am | 76.2% | 0.0% | 211 |
| 10am–11am | Limited data | 24 | |
| 11am–12pm | 78.8% | 2.9% | 34 |
| 12pm–1pm | 68.7% | 2.2% | 184 |
| 1pm–2pm | 92.0% | 0.0% | 75 |
| 2pm–3pm | 82.3% | 0.2% | 413 |
| 3pm–4pm | 71.8% | 4.9% | 41 |
| 5pm–6pm | Limited data | 22 | |
| 6pm–7pm | 62.1% | 0.4% | 236 |
| 8pm–9pm | 53.5% | 15.9% | 69 |
| 9pm–10pm | Limited data | 6 | |
| 10pm–11pm | 78.1% | 1.5% | 66 |
Best day of the week
24 months, by day of departure.
Best month to fly
24 months, by calendar month.
Holiday travel on ORD to SJU
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) | 67.9% | -11.2 pts | 0.0% | 56 |
| Christmas & New Year (Dec 20 - Jan 3) | 71.5% | -7.5 pts | 4.8% | 145 |
| Summer peak (Jun 15 - Aug 15) | 70.8% | -8.3 pts | 1.3% | 472 |
| All other days | 79.0% | — | 1.1% | 1,998 |
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).