Carrier route record
OOBOI→SFO
SkyWest Airlines · Boise to San Francisco
- Flights
- 1,453
- Period
- July 2025 to June 2026
- Share of route
- 86%
- 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 SFO sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 7 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 1,453 flights, with a median arrival 3 minutes early.
The national on-time rate over the same period is 77.6%, so SkyWest on BOI to SFO runs 7 points behind the country as a whole. Across a thousand flights that is about 65 extra late arrivals.
Key figures
On time
71.1%
Arrivals under 15 minutes late, of 1,438 completed flights
Avg delay
77 min
Across delayed arrivals only, not all flights
Cancelled
0.41%
National rate is 1.81%
Whole route
71.2%
Every carrier on BOI to SFO, 1,684 flights
These figures cover 1,453 flights between July 2025 and June 2026. Beyond the headline rate, 11.1% 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
SkyWest against every carrier on BOI to SFO
SkyWest flew 1,453 of the 1,684 flights on BOI to SFO, most of the route. Its 71.1% on time is about level with the route as a whole at 71.2%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from United at 72.4% to SkyWest at 71.1%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
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 |
|---|---|---|---|---|---|
| United Airlinesthin sample | 231 | 72.4% | 115 min | 0.87% | C+ |
| SkyWest Airlines (this page) | 1,453 | 71.1% | 77 min | 0.41% | C+ |
Flight by flight
SkyWest flight numbers on BOI to SFO
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 31 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am293 flights91.8%
- 8am–11am563 flights65.2%
- 11am–2pm168 flights60.5%
- 2pm–5pm176 flights68.2%
- 5pm–8pm253 flights69.0%
- 8pm–5am—
Scale runs 50% 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 60.5% on time against 91.8% 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 8am–11am window is the busiest, with 563 flights scheduled in it.
Across the year
SkyWest on BOI to SFO through the year
Delays peak in May, when the on-time rate falls to 45.9%. August is the strongest month at 90.6%. Moving a flexible trip across that boundary buys 45 points. March was the busiest month here, with 178 flights.
Across the week, Saturday is the strongest day at 83.3% on time and Monday the weakest at 65.3%. 18 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. National Airspace System accounts for 49% of the 32,000 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.
- 49%National Airspace System
- 32%Carrier
- 18%Late-arriving aircraft
- 2%Extreme weather
49% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 16,000 minutes out of 32,000, against a national NAS share of 21%. The split is drawn from 32,091 reported delay minutes.
Cancellations are rare at 0.41%, 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
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 11.1% 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 522 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 75.9% on time across 1,451 flights, 5 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 5 points of difference.
The sample behind these figures is 1,453 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.
What to do with this
Booking SkyWest on BOI to SFO
Put together: the calendar is the biggest lever here, not the carrier or the hour. August runs 90.6% on time and May 45.9%, a swing of 45 points. If the dates move at all, move them out of May before you think about anything else. 1,438 completed flights over 12 months sit behind that.
Related
Where to go next
- BOI to SFO, every carrier
- SkyWest on SFO to BOI, the return leg
- United Airlines on BOI to SFO72.4%
- SkyWest Airlines network-wide record
- San Francisco International (SFO) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- How often a connection fails at the major US hubs
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.