Carrier route record

F9LAX→IAH

Frontier Airlines · Los Angeles to Houston

Flights: 336
Period: September 2025 to August 2026
Share of route: 7%
Carriers: 5

Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Frontier Airlines.

Frontier on LAX to IAH sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 7 points worse than the national rate of 77.3%. The late ones land a little over an hour behind schedule. That rests on 336 flights. The strongest carrier on the route with a full sample, United Airlines, flew 3,420 at 87.4% on time.

United Airlines is the most reliable of the three carriers covered here at 87.4% on time across 3,420 flights.

On time

70.6%

Arrivals under 15 minutes late, of 330 completed flights

Avg delay

74 min

Across delayed arrivals only, not all flights

Cancelled

1.49%

National rate is 1.89%

Whole route

84.6%

Every carrier on LAX to IAH, 5,143 flights

These figures cover 336 flights between September 2025 and August 2026. Beyond the headline rate, 13.9% of arrivals land a full hour or more behind schedule, against 8.3% nationally.

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Carrier by carrier

Frontier against every carrier on LAX to IAH

Frontier flew 336 of the 5,143 flights on LAX to IAH, about 7% of it. Its 70.6% on time is 14 points worse than the route as a whole, which runs 84.6%. Ranked by on-time rate it is last of five carriers on the route, where the range runs from United at 87.4% to Frontier at 70.6%. One 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 87.4% of the time; SkyWest Airlines manages 81.2%. Sample sizes sit next to every figure, because a two-point gap across 408 flights means less than a ten-point one.

On-time performance by carrier on LAX to IAH
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	3,420	87.4%	52 min	0.18%	A+
Delta Air Lines	648	84.8%	70 min	0.93%	B+
SkyWest Airlines	408	81.2%	70 min	0.49%	B+
Spirit Airlinesthin sample	331	73.0%	73 min	1.51%	C
Frontier Airlines (this page)thin sample	336	70.6%	74 min	1.49%	C

United leads SkyWest by 6 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Flight by flight

Frontier flight numbers on LAX to IAH

F9 175618:2570.2% · 310 flights

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Departure window

When Frontier runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 12 points, against 6 points between the best and worst carrier.

5am–8am—
8am–11am61 flights78.0%
11am–2pm103 flights70.6%
2pm–5pm114 flights66.1%
5pm–8pm58 flights71.9%
8pm–5am—

Scale runs 60% to 85%. Rows with fewer than 30 flights show a dash.

Book the morning departure. Flights leaving between 8am–11am arrive on time 78.0% of the time, against 66.1% for the afternoon window. That is 12 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 114 flights scheduled in it.

Across the year

Frontier on LAX to IAH through the year

Jul–Sep 202521 flights—
Oct–Dec 202583 flights63.4%
Jan–Mar 202679 flights68.8%
Apr–Jun 202691 flights74.2%
Jul–Sep 202662 flights73.8%

Scale runs 55% to 80%. 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 70.6% on time across 336 flights.

Frontier on LAX to IAH did not run the same all year. Its best quarter was Apr–Jun 2026 at 74.2% on time and its weakest Oct–Dec 2025 at 63.4%, a swing of 11 points on roughly 84 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, Wednesday is the strongest day at 77.1% on time and Monday the weakest at 60.8%, a spread of 16 points.

Arrival by arrival

How late Frontier on LAX to IAH runs when it is late

The 97 late arrivals split 25 under half an hour, 26 between 30 and 60 minutes, and 46 an hour or more.

15+ min early70 flights21.2%
Within 15 min163 flights49.4%
15–29 min late25 flights7.6%
30–59 min late26 flights7.9%
1–2 hours late28 flights8.5%
2+ hours late18 flights5.5%

Scale runs 0% to 100%.

Share of 330 completed flights by arrival against schedule.

18 of 100 late departures made up the time and arrived on time, 18% of them. 15 flights left on time and still arrived late.

The worst days

Worst days for Frontier on LAX to IAH

The latest arrival of the period was on 7 December 2025, 4 hours 53 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The same cause led on three of the five worst days.

The latest arrivals of Frontier on LAX to IAH in the period
Date	Arrived late by	Largest filed cause
7 December 2025	4 hours 53 minutes	Late-arriving aircraft
21 April 2026	4 hours 17 minutes	Late-arriving aircraft
22 July 2026	3 hours 48 minutes	Carrier
24 December 2025	3 hours 29 minutes	Carrier
19 June 2026	3 hours 17 minutes	Late-arriving aircraft

Delay causes

Why Frontier runs late on this route

Late-arriving aircraft accounts for 51% of the 7,171 delay minutes carriers reported here, and the remaining four split what is left.

Late-arriving aircraft
51%
Carrier
28%
National Airspace System
18%
Extreme weather
2%

51% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 7,171 reported delay minutes here, that single category outweighs weather by 23 to one. The split is drawn from 7,171 reported delay minutes.

The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 78.0% on time here.

Cancellations sit at 1.49% against a national 1.89%, which is ordinary. Diversions add another 0.30%.

Connections and stage length

What a delay here costs

13.9% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.

The 1,379 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.

The return leg runs 71.8% on time across 336 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 336 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 LAX to IAH

Put together: treat all of this as provisional. 336 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 70.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 330 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures