Carrier route record

F9SEA→LAS

Frontier Airlines · Seattle to Las Vegas

Flights: 246
Period: July 2025 to June 2026
Share of route: 4%
Carriers: 6

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

Frontier on SEA to LAS draws a C. About one flight in three arrives at least 15 minutes late, and the typical late arrival is about 2.1 hours behind schedule. Build slack into anything you connect to. That rests on 246 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 1,738 at 83.6% on time.

Delta Air Lines is the most reliable of the three carriers covered here at 83.6% on time across 1,738 flights.

On time

67.9%

Arrivals under 15 minutes late, of 243 completed flights

Avg delay

128 min

Across delayed arrivals only, not all flights

Cancelled

1.22%

National rate is 1.81%

Whole route

77.7%

Every carrier on SEA to LAS, 5,650 flights

These figures cover 246 flights between July 2025 and June 2026. Beyond the headline rate, 12.3% 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 SEA to LAS

Frontier flew 246 of the 5,650 flights on SEA to LAS, about 4% of it. Its 67.9% on time is 10 points worse than the route as a whole, which runs 77.7%. Ranked by on-time rate it is number five of six carriers on the route, where the range runs from SkyWest at 100.0% to Spirit at 67.4%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 83.6% of the time; Southwest Airlines manages 69.2%. Sample sizes sit next to every figure, because a two-point gap across 976 flights means less than a ten-point one.

On-time performance by carrier on SEA to LAS
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlinesthin sample	9	100.0%	—	0.00%	A+
Delta Air Lines	1,738	83.6%	56 min	0.86%	B+
Alaska Airlines	2,638	78.0%	47 min	0.91%	B+
Southwest Airlines	976	69.2%	48 min	0.51%	C+
Frontier Airlines (this page)thin sample	246	67.9%	128 min	1.22%	C
Spirit Airlinesthin sample	43	67.4%	39 min	0.00%	C+

The spread between Delta and Southwest is 14 points, wide enough that it should decide the booking. On a hundred trips that is 14 more arrivals inside the on-time window.

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 17 points, against 14 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am—
11am–2pm48 flights79.2%
2pm–5pm46 flights62.2%
5pm–8pm45 flights63.6%
8pm–5am107 flights67.0%

Scale runs 55% to 85%. Rows with fewer than 30 flights show a dash.

The best window here is not the first bank but the 11am–2pm slot at 79.2% on time, ahead of 2pm–5pm at 62.2%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 8pm–5am window is the busiest, with 107 flights scheduled in it.

Across the year

Frontier on SEA to LAS through the year

Jul–Sep 202550 flights65.3%
Oct–Dec 202561 flights65.0%
Jan–Mar 202669 flights80.9%
Apr–Jun 202666 flights59.1%

Scale runs 50% 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 67.9% on time across 246 flights.

Frontier on SEA to LAS did not run the same all year. Its best quarter was Jan–Mar 2026 at 80.9% on time and its weakest Apr–Jun 2026 at 59.1%, a swing of 22 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, Sunday is the strongest day at 76.9% on time and Monday the weakest at 54.9%. 22 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 50% of the 9,952 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
50%
Late-arriving aircraft
33%
National Airspace System
17%
Extreme weather
1%

The largest share of delay minutes, 50%, 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 4,953 of the 9,952 delay minutes reported here. The split is drawn from 9,952 reported delay minutes.

Cancellations sit at 1.22% 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. 12.3% 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 867 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 82.2% on time across 246 flights, 14 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 14 points of difference.

One caution: this is a thin sample. 246 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 SEA to LAS

Put together: treat all of this as provisional. 246 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 67.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 243 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