Flight number record

AS 358

Alaska Airlines · Portland to Boston

Route: PDX → BOS
Departs: 07:00
Flights: 349
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s AS 358, check with Alaska Airlines.

AS 358 lands a B+, 5 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about 35 minutes on average. That is a workable record, not a spotless one. That rests on 349 flights, with a median arrival 4 minutes early.

Set against the rest of the country, AS 358's record is 5 points better than the US average of 77.6%. That gap is worth roughly 47 fewer late arrivals for every thousand flights.

On time

82.3%

Arrivals under 15 minutes late, of 345 completed flights

Avg delay

36 min

Across delayed arrivals only, not all flights

Cancelled

0.86%

National rate is 1.81%

1 hour+ late

1.7%

National rate is 8.1%

These figures cover 349 flights between July 2025 and June 2026. The median arrival is 4 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.

Schedule

When AS 358 flies

AS 358 flies PDX to BOS without a single fixed slot. Its most common scheduled departure was 07:00, used on 185 of 349 flights, with 07:33 (45 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 07:00185 flights53.0%
Departs 07:3345 flights12.9%

Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.

Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.

A 07:00 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and AS 358 runs 7 points worse at 82.3%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

AS 358 next to PDX to BOS

Every carrier on PDX to BOS combined arrived on time 79.0% of the time across 649 flights, so AS 358 is 3 points ahead of it. Alaska flew 533 flights on the same city pair under all its flight numbers, including this one, and those ran 82.0% on time. Across its whole network Alaska Airlines managed 79.1%, which this flight beats by 3 points.

AS 358 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
AS 358thin sample	349	82.3%	36 min	0.86%	B+
All Alaska Airlines on PDX–BOS	533	82.0%	36 min	0.75%	B+
All carriers on PDX–BOS	649	79.0%	54 min	0.77%	B+
Alaska Airlines, whole network	293,372	79.1%	52 min	1.28%	B

Across the year

AS 358 quarter by quarter

AS 358 did not run the same all year. Its best quarter was Jan–Mar 2026 at 93.1% on time and its weakest Oct–Dec 2025 at 77.8%, a swing of 15 points on roughly 87 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Jul–Sep 202592 flights79.3%
Oct–Dec 202591 flights77.8%
Jan–Mar 202675 flights93.1%
Apr–Jun 202691 flights81.3%

Scale runs 70% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, AS 358 did best on Sunday at 94.1% on time and worst on Tuesday at 75.0%. Each day rests on about 50 flights, so a gap of 19 points is worth noticing but could still narrow in another year.

Delay causes

Why AS 358 runs late

One category carries most of the weight here. National Airspace System accounts for 76% of the 2,182 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.

National Airspace System
76%
Carrier
23%
Late-arriving aircraft
1%

76% 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 1,654 minutes out of 2,182, against a national NAS share of 21%. The split is drawn from 2,182 delay minutes reported on AS 358.

Cancellations are rare at 0.86%, 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 routes

What a delay on this flight costs

Badly late arrivals are rare here: only 1.7% 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 2,537 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.

Every one of the 349 flights under AS 358 in the data flew PDX to BOS. The number was not reused on any other city pair, which makes this a clean record of one route.

One caution: this is a thin sample. 349 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 AS 358

For a booking, read AS 358 as 82.3% on time with 0.86% cancelled over 349 flights. Those are rates from the past twelve months, not a forecast for any particular day.

Where to go next

A flight number here means Alaska Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.

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.

Key figures