Carrier route record
F9LAS→SEA
Frontier Airlines · Las Vegas to Seattle
- 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 LAS to SEA lands a B+, 5 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That is a workable record, not a spotless one. That rests on 246 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 1,738 at 87.6% on time.
Delta Air Lines is the most reliable of the three carriers covered here at 87.6% on time across 1,738 flights.
Key figures
On time
82.2%
Arrivals under 15 minutes late, of 242 completed flights
Avg delay
48 min
Across delayed arrivals only, not all flights
Cancelled
0.81%
National rate is 1.81%
Whole route
82.3%
Every carrier on LAS to SEA, 5,649 flights
These figures cover 246 flights between July 2025 and June 2026. The median arrival is 12 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
Frontier against every carrier on LAS to SEA
Frontier flew 246 of the 5,649 flights on LAS to SEA, about 4% of it. Its 82.2% on time is about level with the route as a whole at 82.3%. Ranked by on-time rate it is number five of six carriers on the route, where the range runs from Spirit at 88.4% to Southwest at 71.0%. 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 87.6% of the time; Southwest Airlines manages 71.0%. Sample sizes sit next to every figure, because a two-point gap across 977 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 43 | 88.4% | 47 min | 0.00% | A+ |
| Delta Air Lines | 1,738 | 87.6% | 87 min | 0.86% | A+ |
| SkyWest Airlinesthin sample | 7 | 85.7% | 59 min | 0.00% | A+ |
| Alaska Airlines | 2,638 | 82.8% | 64 min | 1.25% | B |
| Frontier Airlines (this page)thin sample | 246 | 82.2% | 48 min | 0.81% | B+ |
| Southwest Airlines | 977 | 71.0% | 45 min | 0.31% | C+ |
The spread between Delta and Southwest is 17 points, wide enough that it should decide the booking. On a hundred trips that is 17 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 15 points, against 17 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am82 flights88.9%
- 8am–11am26 flights—
- 11am–2pm72 flights74.3%
- 2pm–5pm33 flights87.5%
- 5pm–8pm33 flights78.8%
- 8pm–5am—
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 74.3% on time against 88.9% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 5am–8am window is the busiest, with 82 flights scheduled in it.
Across the year
Frontier on LAS to SEA through the year
- Jul–Sep 202550 flights77.6%
- Oct–Dec 202561 flights75.0%
- Jan–Mar 202669 flights94.1%
- Apr–Jun 202666 flights80.0%
Scale runs 65% to 100%. 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 82.2% on time across 246 flights.
Frontier on LAS to SEA did not run the same all year. Its best quarter was Jan–Mar 2026 at 94.1% on time and its weakest Oct–Dec 2025 at 75.0%, a swing of 19 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 84.6% on time and Friday the weakest at 76.5%. 8 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 53% of the 2,070 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.
- 53%Late-arriving aircraft
- 26%National Airspace System
- 21%Carrier
53% 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 2,070 reported delay minutes here, that single category outweighs weather by 53 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 2,070 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 88.9% on time here.
Cancellations are rare at 0.81%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 3.3% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
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 67.9% on time across 246 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. 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 LAS to SEA
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 82.2% 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
- LAS to SEA, every carrier
- Frontier on SEA to LAS, the return leg
- Delta Air Lines on LAS to SEA87.6%
- Alaska Airlines on LAS to SEA82.8%
- Southwest Airlines on LAS to SEA71.0%
- Frontier Airlines network-wide record
- Harry Reid International (LAS) delay statistics
- Seattle-Tacoma International (SEA) 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.