Carrier performance at one airport
OO→BOI
SkyWest Airlines at Boise Airport
- Departures
- 10,768
- Period
- June 2025 to May 2026
- Routes
- 13
- Rank here
- #3 of 6
SkyWest Airlines at Boise earns a 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 9 points better than the national rate of 77.4%. When something does go wrong the average delay runs a little over an hour. That rests on 10,768 flights, of which Delta Air Lines flew 2,571 at 88.0% on time.
Measured against the airport rather than the country, SkyWest Airlines runs about a point ahead of the 84.6% weighted average across all carriers at BOI. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
85.9%
10,706 completed departures
Avg delay
69 min
Across delayed flights only
Cancelled
0.39%
At BOI, this carrier only
Rank here
#3
Of 6 carriers clearing the floor at BOI
These figures cover 11,000 flights between June 2025 and May 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.
Against the competition
Every carrier at BOI, ranked
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 88.0% of the time; American Airlines manages 78.3%. Sample sizes sit next to every figure, because a two-point gap across 992 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 2,571 | 88.0% | 84 min | 1.13% | A |
| Alaska Airlines | 2,015 | 87.9% | 55 min | 0.69% | A+ |
| SkyWest Airlines (this page) | 10,768 | 85.9% | 69 min | 0.39% | A+ |
| Southwest Airlines | 5,318 | 81.7% | 54 min | 0.26% | B+ |
| United Airlines | 1,432 | 79.0% | 83 min | 0.56% | B+ |
| American Airlines | 992 | 78.3% | 104 min | 2.32% | B |
Delta leads American by 10 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Route by route
Where SkyWest Airlines flies from BOI
SkyWest Airlines operates 13 routes out of BOI with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| BOI to SEA · Seattle | 2,986 | 86.0% | 57 min | 0.30% | A+ |
| BOI to SFO · San Francisco | 1,442 | 74.1% | 79 min | 0.42% | C+ |
| BOI to LAX · Los Angeles | 1,335 | 93.9% | 73 min | 0.07% | A+ |
| BOI to PHX · Phoenix | 1,005 | 86.1% | 86 min | 0.70% | A+ |
| BOI to DEN · Denver | 862 | 85.4% | 86 min | 0.00% | A+ |
| BOI to PDX · Portland | 517 | 91.8% | 57 min | 0.97% | A+ |
| BOI to SLC · Salt Lake City | 506 | 95.4% | 45 min | 0.20% | A+ |
| BOI to ORD · Chicago | 506 | 83.6% | 71 min | 1.78% | B |
| BOI to SAN · San Diego | 425 | 82.7% | 59 min | 0.47% | B+ |
| BOI to SJC · San Josethin sample | 328 | 92.0% | 66 min | 0.30% | A+ |
| BOI to BUR · Burbankthin sample | 307 | 82.7% | 44 min | 0.00% | B+ |
| BOI to GEG · Spokanethin sample | 306 | 87.5% | 73 min | 0.33% | A+ |
| BOI to LAS · Las Vegasthin sample | 240 | 81.2% | 58 min | 0.00% | B+ |
Departure window
Best time of day for this operation
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 18 points, against 10 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am2,258 flights92.7%
- 8am–11am3,330 flights86.9%
- 11am–2pm1,483 flights83.9%
- 2pm–5pm1,719 flights84.1%
- 5pm–8pm1,705 flights80.1%
- 8pm–5am273 flights74.3%
Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 92.7% of the time, against 74.3% for the overnight window. That is 18 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on.
Across the year
Seasonal pattern
October is the best month on the calendar at 88.3% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back.
Delay causes
What holds this operation up
- 45%Carrier
- 26%National Airspace System
- 21%Late-arriving aircraft
- 8%Extreme weather
- 0%Security
The largest share of delay minutes, 45%, 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 47,000 of the 105,000 delay minutes reported here.
Cancellations are rare at 0.39%, below the national 1.80% 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.
Badly late arrivals are rare here: only 4.6% land an hour or more behind schedule, against 8.2% 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 sample behind these figures is 10,768 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
Put together: avoid the 8pm–5am departure. It runs 74.3% on time against 92.7% for the 5am–8am slot, and that 18 points is the largest single thing you control here. Delta Air Lines is the strongest operator if the fares are close.
Common questions
SkyWest Airlines at BOI
How often is SkyWest Airlines at BOI delayed?
About one flight in seven arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 14.1% of the 10,768 flights in this analysis, against 22.6% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on SkyWest Airlines at BOI?
Delta Air Lines leads at 88.0% on time across 2,571 flights. American Airlines is at the other end on 78.3%, a gap of 10 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on SkyWest Airlines at BOI?
The 5am–8am departure window is the strongest at 92.7% on time. The 8pm–5am window is the weakest at 74.3%, 18 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are May delays on SkyWest Airlines at BOI?
May is the weakest month at 81.1% on time, compared with 88.3% in October. Across the year that is 7 points between the best and worst months. The seasonal swing is modest enough that it should not decide when you travel.
Related
Where to go next
Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.