Carrier route record
F9ORD→IAH
Frontier Airlines · Chicago to Houston
- Flights
- 249
- Period
- July 2025 to June 2026
- Share of route
- 4%
- Carriers
- 8
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier on ORD to IAH lands a B, 2 points worse than the national rate of 77.6%. About one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 249 flights. The strongest carrier on the route with a full sample, United Airlines, flew 4,000 at 78.6% on time.
The US average over the same twelve months is 77.6%, so there is little to separate Frontier on ORD to IAH from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
76.0%
Arrivals under 15 minutes late, of 242 completed flights
Avg delay
96 min
Across delayed arrivals only, not all flights
Cancelled
2.41%
National rate is 1.81%
Whole route
75.0%
Every carrier on ORD to IAH, 6,077 flights
These figures cover 249 flights between July 2025 and June 2026. Beyond the headline rate, 14.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Frontier against every carrier on ORD to IAH
Frontier flew 249 of the 6,077 flights on ORD to IAH, about 4% of it. Its 76.0% on time is about level with the route as a whole at 75.0%. Ranked by on-time rate it is number three of eight carriers on the route, where the range runs from United at 78.6% to SkyWest at 0.0%. Five of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. United Airlines arrives on time 78.6% of the time; American Airlines manages 60.6%. Sample sizes sit next to every figure, because a two-point gap across 798 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 4,000 | 78.6% | 67 min | 0.65% | B+ |
| Republic Airwaysthin sample | 359 | 76.3% | 69 min | 2.51% | B |
| Frontier Airlines (this page)thin sample | 249 | 76.0% | 96 min | 2.41% | B |
| Envoy Airthin sample | 358 | 74.4% | 63 min | 1.40% | C |
| Spirit Airlinesthin sample | 307 | 63.1% | 102 min | 5.54% | D− |
| American Airlines | 798 | 60.6% | 84 min | 3.01% | D− |
| PSA Airlinesthin sample | 4 | 50.0% | 74 min | 0.00% | F+ |
| SkyWest Airlinesthin sample | 2 | 0.0% | 32 min | 0.00% | F+ |
American Airlines cancels 3.0% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Departure window
When Frontier runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 249 flights.
- 5am–8am101 flights79.4%
- 8am–11am24 flights—
- 11am–2pm32 flights71.0%
- 2pm–5pm65 flights70.8%
- 5pm–8pm24 flights—
- 8pm–5am3 flights—
Scale runs 60% to 85%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 79.4% of the time, against 70.8% for the afternoon window. That is 9 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 101 flights scheduled in it.
Across the year
Frontier on ORD to IAH through the year
- Jul–Sep 202552 flights70.6%
- Oct–Dec 202560 flights72.9%
- Jan–Mar 202649 flights85.1%
- Apr–Jun 202688 flights76.5%
Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 76.0% on time across 249 flights.
Frontier on ORD to IAH did not run the same all year. Its best quarter was Jan–Mar 2026 at 85.1% on time and its weakest Jul–Sep 2025 at 70.6%, a swing of 15 points on roughly 62 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
Across the week, Monday is the strongest day at 82.9% on time and Friday the weakest at 72.3%. 11 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Frontier runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 52% of the 5,553 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 52%Late-arriving aircraft
- 24%Carrier
- 20%National Airspace System
- 4%Extreme weather
52% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 5,553 reported delay minutes here, that single category outweighs weather by 13 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 5,553 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 79.4% on time here.
Cancellations sit at 2.41% against a national 1.81%, which is ordinary. Diversions add another 0.40%.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 14.5% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
The 925 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 61.8% on time across 248 flights, 14 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 14 points of difference.
One caution: this is a thin sample. 249 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking Frontier on ORD to IAH
Put together: treat all of this as provisional. 249 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 76.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 242 completed flights over 12 months sit behind that.
Related
Where to go next
- ORD to IAH, every carrier
- Frontier on IAH to ORD, the return leg
- United Airlines on ORD to IAH78.6%
- Republic Airways on ORD to IAH76.3%
- Envoy Air on ORD to IAH74.4%
- Spirit Airlines on ORD to IAH63.1%
- American Airlines on ORD to IAH60.6%
- Frontier Airlines network-wide record
- Chicago O'Hare International (ORD) delay statistics
- George Bush Intercontinental (IAH) delay statistics
- Why the first flight of the morning is statistically safest
- Same route, different airline: where the carrier you pick matters most
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.