87% of flights from Boise to San Jose arrived on time over the past 12 months. That is better than the typical U.S. route. The 10 a.m. departures ran on time 94% of the time; the 7 a.m. ones 91%. Most reliable airline: Alaska Airlines (93%). 4% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for BOI → SJC: when a flight was late, it was under 45 minutes late 67% of the time. About 1 in 29 flights landed an hour or more late, and 1 in 172 three hours or more; 0.1% were cancelled outright.
- On time or early87%
- 15–30 min late6.0%
- 30–60 min late3.3%
- 1–2 hours late2.5%
- 2–3 hours late0.4%
- 3+ hours late0.6%
- Diverted0.0%
- Cancelled0.1%
Share of all 687 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| Alaska Airlines | 357 | 93% | 0.3% | −10 min | 2.2% | +73 min | SkyWest 88%, Horizon Air 12% |
| Southwest Airlines | 330 | 80% | 0.0% | −5 min | 4.8% | +49 min | Southwest Airlines |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at BOI). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | Alaska Airlines |
|---|---|
| 7 a.m. | 91% |
| 10 a.m. | 94% |
By month
Each calendar month pooled over 2023–2026. Best: September (91%). Worst: June (82%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 109 | 82% | 0.0% |
| Tuesday | 94 | — | — |
| Wednesday | 92 | — | — |
| Thursday | 104 | 89% | 0.0% |
| Friday | 107 | 84% | 0.9% |
| Saturday | 69 | — | — |
| Sunday | 112 | 88% | 0.0% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 1
Month by month
Not enough months with data to draw a trend.
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Dec 23, 2025 | 3 | 33% | 0 |
| Dec 30, 2025 | 3 | 33% | 0 |
| Nov 26, 2025 | 3 | 67% | 0 |
| Dec 26, 2025 | 3 | 67% | 0 |
| Nov 25, 2025 | 3 | 67% | 0 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Boise or San Jose. None has been clearly more reliable than BOI → SJC.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| BOI → SJC (this route) | 687 | 87% | 0.1% |
| BOI → OAK Boise /Gowen to Oakland | 529 | 83% | 0.0% |
| BOI → SFO Boise /Gowen to San Francisco | 1,827 | 65% | 0.5% |
Questions
How often are flights from BOI to SJC on time?
87% of 687 scheduled flights from Boise, ID to San Jose, CA arrived within 15 minutes of schedule between September 2025 and August 2026. 0.1% were cancelled.
What is the best time of day to fly BOI to SJC?
Flights scheduled to leave at 10 a.m. were the most reliable (94% on time). The 7 a.m. departures were the least (91%).
Which airline is most on time from BOI to SJC?
Alaska Airlines: 93% of its 357 flights on the route arrived on time. Southwest Airlines: 80%.
What month has the most delays from BOI to SJC?
June (82% on time). The best month is September (91%), over 2023–2026.
Related
- SJC → BOI (return)
- Boise /Gowen (BOI) delays by hour
- Flights into San Jose (SJC)
- Alaska Airlines on-time record
- Southwest Airlines on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.