Houston (IAH) to Chicago (ORD): On-Time Performance
Data through May 2026
Houston (IAH) to Chicago (ORD) effectively runs on two schedules. In October 2024, 89% of arrivals were on time; in July 2024 that fell to 59% — a 30-point seasonal swing. Across the full period the route averages 77% on-time against a national 78%. Morning departures also hold up better than evening ones (86% vs 67%), which matters most in the rough months.
- On-time
- 77%
- arrived <15 min late
- Avg delay
- 20 min
- completed flights
- Cancelled
- 1.4%
- Flights/day
- 17
- last 12 months
- Duration
- 2h 47m
- scheduled
- Distance
- 925 mi
Best airline from IAH to ORD
6 airlines flew this route regularly between 2024-06 and 2026-05.
| Airline | On-time | Avg delay | Cancelled | Flights |
|---|---|---|---|---|
| United Airlinesmost reliable | 80% | 15 min | 0.9% | 7,785 |
| Envoy Air | 73% | 20 min | 1.3% | 473 |
| Republic Airways | 72% | 25 min | 3.1% | 522 |
| American Airlines | 72% | 32 min | 2.5% | 1,513 |
| Spirit Airlines | 70% | 22 min | 2.7% | 951 |
| Frontier Airlines | 58% | 52 min | 3.8% | 418 |
Monthly on-time trend
Best time to fly from IAH to ORD
Aim for departures around 5 a.m. (92% on-time); avoid 4 p.m. departures (56%).
By day of week
| Day | On-time | Avg delay |
|---|---|---|
| Monday | 76% | 25 min |
| Tuesdaybest | 79% | 16 min |
| Wednesday | 78% | 18 min |
| Thursday | 77% | 18 min |
| Friday | 75% | 20 min |
| Saturday | 78% | 20 min |
| Sunday | 73% | 20 min |
What causes delays on this route
Share of total delay minutes by cause, as reported by carriers to the US DOT.
- Late-arriving aircraft40%
- Airline operations26%
- National airspace system26%
- Weather8%
Frequently asked questions
- How often are flights from IAH to ORD delayed?
- 24% of IAH–ORD flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 20 minutes.
- Which airline is most reliable from IAH to ORD?
- United Airlines has the best on-time record on this route at 80%, based on 7,785 flights. 6 airlines flew IAH–ORD frequently enough to compare in this period.
- What is the best time of day to fly from IAH to ORD?
- Departures around 5 a.m. have the best record (92% on-time), while departures around 4 p.m. have the worst (56%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
- How long is the flight from IAH to ORD?
- The scheduled IAH–ORD flight time averages 2h 47m over 925 miles. Actual arrival times vary — flights on this route land 15+ minutes late 24% of the time.
- How often are IAH to ORD flights cancelled?
- 1.4% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
- What is the worst month to fly from IAH to ORD?
- July 2024 was the roughest month in this dataset, with only 59% of arrivals on time. The best was October 2024 at 89%. If your dates are flexible, that 30-point gap is worth planning around.
Explore related pages
More routes from IAH
Based on 11,669 flights, 2024-06–2026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.