Carrier route record

ASIAD→SAN

Alaska Airlines · Washington to San Diego

Flights: 361
Period: September 2025 to August 2026
Share of route: 26%
Carriers: 2

Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Alaska Airlines.

Alaska on IAD to SAN sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.3%. The late ones land roughly 50 minutes behind schedule. That rests on 361 flights, with a median arrival 6 minutes early.

The US average over the same twelve months is 77.3%, so there is little to separate Alaska on IAD to SAN from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

73.4%

Arrivals under 15 minutes late, of 354 completed flights

Avg delay

48 min

Across delayed arrivals only, not all flights

Cancelled

0.83%

National rate is 1.89%

Whole route

82.9%

Every carrier on IAD to SAN, 1,402 flights

These figures cover 361 flights between September 2025 and August 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.

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Carrier by carrier

Alaska against every carrier on IAD to SAN

Alaska flew 361 of the 1,402 flights on IAD to SAN, about 26% of it. Its 73.4% on time is 10 points worse than the route as a whole, which runs 82.9%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from United at 86.1% to Alaska at 73.4%.

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.

On-time performance by carrier on IAD to SAN
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	1,041	86.1%	65 min	0.67%	A+
Alaska Airlines (this page)thin sample	361	73.4%	48 min	0.83%	C+

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Departure window

When Alaska runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 12 points, against half a point between the best and worst carrier.

5am–8am—
8am–11am—
11am–2pm—
2pm–5pm—
5pm–8pm319 flights74.8%
8pm–5am42 flights62.5%

Scale runs 55% to 80%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 62.5% on time, against 74.8% for the 5pm–8pm slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 5pm–8pm window is the busiest, with 319 flights scheduled in it.

Across the year

Alaska on IAD to SAN through the year

Jul–Sep 202530 flights—
Oct–Dec 202588 flights75.6%
Jan–Mar 202690 flights75.3%
Apr–Jun 202691 flights73.6%
Jul–Sep 202662 flights67.8%

Scale runs 60% to 80%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 73.4% on time across 361 flights.

Quarter by quarter Alaska on IAD to SAN held fairly steady: 75.6% in Oct–Dec 2025, 75.3% in Jan–Mar 2026, 73.6% in Apr–Jun 2026 and 67.8% in Jul–Sep 2026. A spread of 8 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Across the week, Saturday is the strongest day at 87.8% on time and Thursday the weakest at 65.3%, a spread of 23 points.

Arrival by arrival

How late Alaska on IAD to SAN runs when it is late

Alaska on IAD to SAN often beats the schedule: 123 of 354 completed flights, 35%, arrived 15 minutes or more early. The 94 late arrivals split 36 under half an hour, 39 between 30 and 60 minutes, and 19 an hour or more.

15+ min early123 flights34.7%
Within 15 min137 flights38.7%
15–29 min late36 flights10.2%
30–59 min late39 flights11.0%
1–2 hours late16 flights4.5%
2+ hours late3 flights0.8%

Scale runs 0% to 100%.

Share of 354 completed flights by arrival against schedule.

A late pushback is often recovered here: of 66 departures that left 15 minutes late or more, 24 still arrived on time. In the other direction, 52 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at SAN.

The worst days

Worst days for Alaska on IAD to SAN

The latest arrival of the period was on 19 July 2026, 8 hours 23 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The five worst days are spread across July, November, March and June, with no single month standing out.

The latest arrivals of Alaska on IAD to SAN in the period
Date	Arrived late by	Largest filed cause
19 July 2026	8 hours 23 minutes	Late-arriving aircraft
18 November 2025	2 hours 40 minutes	Carrier
13 March 2026	2 hours 20 minutes	Late-arriving aircraft
12 June 2026	1 hour 50 minutes	National Airspace System
14 June 2026	1 hour 47 minutes	National Airspace System

Delay causes

Why Alaska runs late on this route

National Airspace System accounts for 49% of the 4,542 delay minutes carriers reported here, and the remaining four split what is left.

National Airspace System
49%
Late-arriving aircraft
34%
Carrier
9%
Extreme weather
7%
Security
1%

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 2,229 minutes out of 4,542, against a national NAS share of 21%. The split is drawn from 4,542 reported delay minutes.

Cancellations are rare at 0.83%, below the national 1.89% 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

5.4% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last roughly 50 minutes, which a normal layover absorbs.

At 2,253 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.

The return leg is a different operation and performs like one: it runs 86.3% on time across 361 flights, 13 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 13 points of difference.

One caution: this is a thin sample. 361 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 IAD to SAN

Put together: treat all of this as provisional. 361 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 73.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 354 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures