Flight number record

AS 505

Alaska Airlines · Seattle to Los Angeles

Route: SEA → LAX
Departs: 09:00
Flights: 337
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s AS 505, check with Alaska Airlines.

AS 505 lands a B+, 6 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 40 minutes on average. That is a workable record, not a spotless one. That rests on 337 flights, with a median arrival 4 minutes early.

Set against the rest of the country, AS 505's record is 6 points better than the US average of 77.6%. That gap is worth roughly 60 fewer late arrivals for every thousand flights.

On time

83.6%

Arrivals under 15 minutes late, of 336 completed flights

Avg delay

40 min

Across delayed arrivals only, not all flights

Cancelled

0.30%

National rate is 1.81%

1 hour+ late

2.7%

National rate is 8.1%

These figures cover 337 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 505 flies

AS 505 flies SEA to LAX without a single fixed slot. Its most common scheduled departure was 09:00, used on 50 of 337 flights, with 10:17 (50 flights) and 10:59 (48 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 09:0050 flights14.8%
Departs 10:1750 flights14.8%
Departs 10:5948 flights14.2%

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 09:00 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and AS 505 runs level with that at 83.6%. 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 505 next to SEA to LAX

Every carrier on SEA to LAX combined arrived on time 83.4% of the time across 7,428 flights, so AS 505 is about level with it. Alaska flew 3,282 flights on the same city pair under all its flight numbers, including this one, and those ran 81.0% on time. Across its whole network Alaska Airlines managed 79.1%, which this flight beats by 5 points.

AS 505 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
AS 505thin sample	337	83.6%	40 min	0.30%	B+
All Alaska Airlines on SEA–LAX	3,282	81.0%	43 min	1.07%	B
All carriers on SEA–LAX	7,428	83.4%	59 min	0.92%	B+
Alaska Airlines, whole network	293,372	79.1%	52 min	1.28%	B

Across the year

AS 505 quarter by quarter

AS 505 did not run the same all year. Its best quarter was Apr–Jun 2026 at 90.5% on time and its weakest Jan–Mar 2026 at 78.7%, a swing of 12 points on roughly 84 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 202590 flights84.4%
Oct–Dec 202573 flights80.8%
Jan–Mar 202690 flights78.7%
Apr–Jun 202684 flights90.5%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, AS 505 ranged from 78.3% on Tuesday to 88.5% on Monday. With about 48 flights behind each day, a spread of 10 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why AS 505 runs late

One category carries most of the weight here. Carrier accounts for 42% of the 2,185 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.

Carrier
42%
National Airspace System
26%
Late-arriving aircraft
24%
Extreme weather
8%

The largest share of delay minutes, 42%, 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 921 of the 2,185 delay minutes reported here. The split is drawn from 2,185 delay minutes reported on AS 505.

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 routes

What a delay on this flight costs

Badly late arrivals are rare here: only 2.7% 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.

The 954 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.

Every one of the 337 flights under AS 505 in the data flew SEA to LAX. 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. 337 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 505

For a booking, read AS 505 as 83.6% on time with 0.30% cancelled over 337 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