Carrier route record
ASPDX→BOI
Alaska Airlines · Portland to Boise
- Flights
- 659
- Period
- July 2025 to June 2026
- Share of route
- 73%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Alaska Airlines.
Alaska on PDX to BOI 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 roughly 45 minutes. That rests on 659 flights, with a median arrival 6 minutes early.
Set against the rest of the country, Alaska's PDX to BOI record is 8 points better than the US average of 77.6%. That gap is worth roughly 81 fewer late arrivals for every thousand flights.
Key figures
On time
85.7%
Arrivals under 15 minutes late, of 657 completed flights
Avg delay
44 min
Across delayed arrivals only, not all flights
Cancelled
0.30%
National rate is 1.81%
Whole route
86.7%
Every carrier on PDX to BOI, 908 flights
These figures cover 659 flights between July 2025 and June 2026. The median arrival is 6 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
Alaska against every carrier on PDX to BOI
Alaska flew 659 of the 908 flights on PDX to BOI, most of the route. Its 85.7% on time is about level with the route as a whole at 86.7%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from SkyWest at 89.3% to Alaska at 85.7%. 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 |
|---|---|---|---|---|---|
| SkyWest Airlinesthin sample | 249 | 89.3% | 63 min | 2.01% | A |
| Alaska Airlines (this page) | 659 | 85.7% | 44 min | 0.30% | A+ |
Departure window
When Alaska 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 659 flights.
- 5am–8am—
- 8am–11am36 flights91.7%
- 11am–2pm—
- 2pm–5pm326 flights86.5%
- 5pm–8pm37 flights83.8%
- 8pm–5am260 flights84.1%
Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.
The early departures do better, though not dramatically: 91.7% on time for the 8am–11am window against 83.8% for 5pm–8pm. Worth taking if the schedule allows, not worth an extra connection. The 2pm–5pm window is the busiest, with 326 flights scheduled in it.
Across the year
Alaska on PDX to BOI through the year
December is the weak month at 76.3% on time, against 91.4% in April. 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. January was the busiest month here, with 97 flights.
Across the week, Tuesday is the strongest day at 91.0% on time and Sunday the weakest at 82.4%. 9 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Alaska runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 54% of the 4,100 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.
- 54%Late-arriving aircraft
- 30%Carrier
- 15%National Airspace System
- 0%Extreme weather
54% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 4,100 reported delay minutes here, that single category outweighs weather by 54 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 4,100 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 91.7% on time here.
Cancellations are rare at 0.30%, 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 3.2% 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 344 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 is a different operation and performs like one: it runs 91.6% on time across 658 flights, 6 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 6 points of difference.
One caution: this is a thin sample. 659 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 Alaska on PDX to BOI
Put together: treat all of this as provisional. 659 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 85.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 657 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.