Carrier route record

F9IAH→LAS

Frontier Airlines · Houston to Las Vegas

Flights: 328
Period: July 2025 to June 2026
Share of route: 9%
Carriers: 3

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

Frontier on IAH to LAS sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 6 points worse than the national rate of 77.6%. The late ones land about 2.1 hours behind schedule. That rests on 328 flights. The strongest carrier on the route with a full sample, United Airlines, flew 2,602 at 83.9% on time.

The national on-time rate over the same period is 77.6%, so Frontier on IAH to LAS runs 6 points behind the country as a whole. Across a thousand flights that is about 59 extra late arrivals.

On time

71.7%

Arrivals under 15 minutes late, of 321 completed flights

Avg delay

126 min

Across delayed arrivals only, not all flights

Cancelled

2.13%

National rate is 1.81%

Whole route

82.4%

Every carrier on IAH to LAS, 3,457 flights

These figures cover 328 flights between July 2025 and June 2026. Beyond the headline rate, 12.1% 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 IAH to LAS

Frontier flew 328 of the 3,457 flights on IAH to LAS, about 9% of it. Its 71.7% on time is 11 points worse than the route as a whole, which runs 82.4%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from United at 83.9% to Frontier at 71.7%.

The two carriers here are closely matched: 2 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.

On-time performance by carrier on IAH to LAS
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	2,602	83.9%	59 min	0.38%	B+
Spirit Airlines	527	81.9%	78 min	2.09%	B
Frontier Airlines (this page)thin sample	328	71.7%	126 min	2.13%	C

No carrier stands out. United tops the table at 83.9%, 2 points clear of the bottom, which is inside the range this kind of sample moves year to year.

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 25 points, against 2 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am7 flights—
11am–2pm74 flights85.5%
2pm–5pm27 flights—
5pm–8pm86 flights75.3%
8pm–5am134 flights60.2%

Scale runs 50% to 90%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 60.2% on time, against 85.5% for the 11am–2pm slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8pm–5am window is the busiest, with 134 flights scheduled in it.

Across the year

Frontier on IAH to LAS through the year

Jul–Sep 202558 flights70.2%
Oct–Dec 202561 flights72.1%
Jan–Mar 202660 flights79.3%
Apr–Jun 2026149 flights69.0%

Scale runs 60% to 85%. 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 71.7% on time across 328 flights.

Frontier on IAH to LAS did not run the same all year. Its best quarter was Jan–Mar 2026 at 79.3% on time and its weakest Apr–Jun 2026 at 69.0%, a swing of 10 points on roughly 82 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, Saturday is the strongest day at 79.4% on time and Friday the weakest at 60.7%. 19 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. Carrier accounts for 54% of the 11,000 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.

Carrier
54%
Late-arriving aircraft
34%
National Airspace System
11%
Extreme weather
1%

The largest share of delay minutes, 54%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 6,168 of the 11,000 delay minutes reported here. The split is drawn from 11,498 reported delay minutes.

Cancellations sit at 2.13% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

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. 12.1% 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 1,222 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 80.2% on time across 328 flights, 9 points above 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 9 points of difference.

One caution: this is a thin sample. 328 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 IAH to LAS

Put together: treat all of this as provisional. 328 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 71.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 321 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures