Carrier route record
OOBOI→DEN
SkyWest Airlines · Boise to Denver
- Flights
- 871
- Period
- July 2025 to June 2026
- Share of route
- 29%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.
SkyWest on BOI to DEN earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs an hour and a half. That rests on 871 flights. The strongest carrier on the route with a full sample, United Airlines, flew 946 at 80.1% on time.
Set against the rest of the country, SkyWest's BOI to DEN record is 8 points better than the US average of 77.6%. That gap is worth roughly 82 fewer late arrivals for every thousand flights.
Key figures
On time
85.8%
Arrivals under 15 minutes late, of 871 completed flights
Avg delay
86 min
Across delayed arrivals only, not all flights
Cancelled
0.00%
National rate is 1.81%
Whole route
80.9%
Every carrier on BOI to DEN, 3,035 flights
These figures cover 871 flights between July 2025 and June 2026. The median arrival is 9 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
SkyWest against every carrier on BOI to DEN
SkyWest flew 871 of the 3,035 flights on BOI to DEN, about 29% of it. Its 85.8% on time is 5 points better than the route as a whole, which runs 80.9%. Ranked by on-time rate it is first of four carriers on the route, where the range runs from SkyWest at 85.8% to Southwest at 77.8%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines (this page) | 871 | 85.8% | 86 min | 0.00% | A+ |
| Frontier Airlinesthin sample | 126 | 80.2% | 141 min | 0.00% | B+ |
| United Airlines | 946 | 80.1% | 89 min | 0.53% | B+ |
| Southwest Airlines | 1,092 | 77.8% | 56 min | 0.09% | B+ |
No carrier stands out. United tops the table at 80.1%, 2 points clear of the bottom, which is inside the range this kind of sample moves year to year.
Departure window
When SkyWest runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 16 points, against 2 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am288 flights91.7%
- 8am–11am310 flights89.0%
- 11am–2pm—
- 2pm–5pm—
- 5pm–8pm273 flights75.8%
- 8pm–5am—
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 91.7% of the time, against 75.8% for the evening window. That is 16 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 310 flights scheduled in it.
Across the year
SkyWest on BOI to DEN through the year
December is the weak month at 79.3% on time, against 94.9% in June. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. March was the busiest month here, with 93 flights.
Across the week, Wednesday is the strongest day at 92.0% on time and Friday the weakest at 75.6%. 16 points is a smaller lever than departure hour, but it is free.
Delay causes
Why SkyWest runs late on this route
One category carries most of the weight here. Carrier accounts for 48% 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.
- 48%Carrier
- 23%Late-arriving aircraft
- 22%National Airspace System
- 7%Extreme weather
The largest share of delay minutes, 48%, 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 5,096 of the 11,000 delay minutes reported here. The split is drawn from 10,618 reported delay minutes.
Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
5.6% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last an hour and a half, which a normal layover absorbs.
The 649 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 78.7% on time across 874 flights, 7 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 7 points of difference.
One caution: this is a thin sample. 871 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 SkyWest on BOI to DEN
Put together: treat all of this as provisional. 871 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 85.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 871 completed flights over 12 months sit behind that.
Related
Where to go next
- BOI to DEN, every carrier
- SkyWest on DEN to BOI, the return leg
- Frontier Airlines on BOI to DEN80.2%
- United Airlines on BOI to DEN80.1%
- Southwest Airlines on BOI to DEN77.8%
- SkyWest Airlines network-wide record
- Denver International (DEN) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
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.