Carrier route record
OOBOI→SLC
SkyWest Airlines · Boise to Salt Lake City
- Flights
- 517
- Period
- July 2025 to June 2026
- Share of route
- 30%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with SkyWest Airlines.
SkyWest on BOI to SLC earns an A+. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 18 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 45 minutes. That rests on 517 flights, with a median arrival 16 minutes early.
Set against the rest of the country, SkyWest's BOI to SLC record is 18 points better than the US average of 77.6%. That gap is worth roughly 177 fewer late arrivals for every thousand flights.
Key figures
On time
95.3%
Arrivals under 15 minutes late, of 515 completed flights
Avg delay
47 min
Across delayed arrivals only, not all flights
Cancelled
0.19%
National rate is 1.81%
Whole route
92.0%
Every carrier on BOI to SLC, 1,740 flights
These figures cover 517 flights between July 2025 and June 2026. The median arrival is 16 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 SLC
SkyWest flew 517 of the 1,740 flights on BOI to SLC, about 30% of it. Its 95.3% on time is 3 points better than the route as a whole, which runs 92.0%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from SkyWest at 95.3% to Delta at 90.5%.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlines (this page) | 517 | 95.3% | 47 min | 0.19% | A+ |
| Delta Air Lines | 1,223 | 90.5% | 93 min | 1.31% | A |
Departure window
When SkyWest runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 517 flights.
- 5am–8am6 flights—
- 8am–11am253 flights97.2%
- 11am–2pm54 flights94.4%
- 2pm–5pm—
- 5pm–8pm204 flights93.1%
- 8pm–5am—
Scale runs 85% to 100%. Rows with fewer than 30 flights show a dash.
The early departures do better, though not dramatically: 97.2% on time for the 8am–11am window against 93.1% for 5pm–8pm. Worth taking if the schedule allows, not worth an extra connection. The 8am–11am window is the busiest, with 253 flights scheduled in it.
Across the year
SkyWest on BOI to SLC through the year
January is the weak month at 88.9% on time, against 100.0% in November. 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. December was the busiest month here, with 66 flights.
Across the week, Monday is the strongest day at 97.3% on time and Thursday the weakest at 91.2%. 6 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 64% of the 1,137 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.
- 64%Carrier
- 28%Extreme weather
- 8%National Airspace System
Extreme weather accounts for 28% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 4.5 times the usual weather exposure. The split is drawn from 1,137 reported delay minutes.
The largest share of delay minutes, 64%, 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 724 of the 1,137 delay minutes reported here.
Cancellations are rare at 0.19%, 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 1.0% 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.
At 290 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8am–11am window matters as much as it does.
The return leg runs 92.6% on time across 519 flights, within 3 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 517 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 SLC
Put together: treat all of this as provisional. 517 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 95.3% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 515 completed flights over 12 months sit behind that.
Related
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.