SAN → SEA Flight Reliability

Right now

Origin · SANNo disruption reported

Aviation weather is not currently a factor.

Updated 08:51 UTC

San Diego airport profile →

Destination · SEANo disruption reported

Aviation weather is not currently a factor.

Updated 08:53 UTC

Seattle airport profile →

Route reliability

July 2023 – July 2026

Route Reliability Score

73/ 100Good

Better than 69% of comparable major US routes (4,598 compared)

Calculated from 14,319 flights. How this is calculated

On-time arrivals

81.5%

11,520 of 14,130

Cancellation rate

1.24%

178 cancelled

Median arrival delay

-7 min

Average 2.7 min

Severe delays

5.3%

60+ minutes late

Delay when late

64 min

Average, when 15+ min late

Flights analyzed

14,319

2 carriers

SAN → SEA arrives on time 81.5% of the time; the return trip, SEA → SAN, arrives on time 78.5% of the time, a 3.0-point gap between the two directions of the same city pair.

SAN → SEA spends 35.5 minutes on the ground on a 1,050-mile trip: 23.2 minutes from pushback to wheels-up at SAN and 12.3 minutes from touchdown to gate at SEA.

Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026

Why SAN → SEA flights are cancelled

July 2023 – July 2026

SAN → SEA cancelled 178 of 14,319 scheduled flights — about 1 in every 80. The reason filed most often was the airline, 73.0% of the cancellations coded on this route — about 1 in every 110 scheduled flights.

Share of cancellations

Airline73.0%

Weather22.5%

Air traffic4.5%

Security0.0%

Of 178 cancelled departures carrying a reason code.

What each reason means

The airline1 in 110

Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.

130 cancellations, 73.0% of the total.

Extreme weather1 in 358

Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.

40 cancellations, 22.5% of the total.

The air traffic system1 in 1,790

Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.

8 cancellations, 4.5% of the total.

Security—

A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.

0 cancellations, 0.0% of the total.

Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. With only one or two carriers on the route, the split mostly reflects how they file. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.

178 coded cancellations were recorded on SAN → SEA; the section appears from 50.

When it goes wrong

July 2023 – July 2026

One arrival in ten is worse than

33 min late

against a median of 7 min early

Arrived an hour or more late5.3%

Typical delay when late64 min

Cancelled1.24%

Landed somewhere else0.08%

Percentiles over 14,319 operations; cancelled and diverted flights are counted separately.

Will your connection be tight enough?

Layovers at SEA after arriving from SAN.

Connection buffer and chance of missing by layover length, SAN → SEA arrivals
Connection time	Chance of missing	Reads as
30 min	35%	Likely to miss
45 min	18%	High risk
60 min	11%	Some risk
90 min	5.3%	Some risk
120 min	3.0%	Low risk

This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 1.24% of the time and diverts 0.08% of the time, which a late arrival never shows up in.

Chance of missing is the share of 14,130 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.

The worst tenth of arrivals on this route land at least 33 minutes late (90th-percentile gate arrival delay), over 14,319 operations.

Any other layover length: connection checker.

Best time to fly

SAN → SEA flights departing 5–9 AM arrived on time 86.9% of the time, against 75.2% for 6–9 PM departures, a gap of 11.7 percentage points.

By day and hour

On-time arrival rate for each weekday and scheduled departure hour, in local time at the departure airport (SAN).

Hour of departure and day of the week matter about equally: hourly averages sit a typical 4.9 points from the route-wide rate, weekday averages 3.3 points.

On-time arrival rate for SAN to SEA by weekday and scheduled departure hour, local time. Each button reads out one slot.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
6 AM–7 AM
7 AM–8 AM
8 AM–9 AM
9 AM–10 AM
10 AM–11 AM
11 AM–12 PM
12 PM–1 PM
1 PM–2 PM
2 PM–3 PM
3 PM–4 PM
4 PM–5 PM
5 PM–6 PM
6 PM–7 PM
7 PM–8 PM
8 PM–9 PM

On-time rate, % · stronger color, fewer on time

65–69
70–74
75–79
80–84
85–89
90–94
95–99

Fewer than 120 flights, not scored

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · On time is arrival within 15 minutes of schedule. Cells round to whole percentages; the table shows one decimal.

No slot is named best or worst: too few reach 500 flights. Departures after 9 PM (45 flights) are not drawn: no slot in those hours has enough flights to score.

View as tableHide table

On-time arrival rate (%) with flights beneath, by scheduled departure hour and weekday for SAN to SEA. A dash means fewer than 120 flights, which are not scored.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
6 AM–7 AM	95.3% on time174 flights	92.9% on time129 flights	90.6% on time130 flights	94.5% on time168 flights	90.0% on time165 flights	94.0% on time120 flights	91.8% on time163 flights
7 AM–8 AM	85.3% on time258 flights	89.7% on time224 flights	90.2% on time224 flights	83.1% on time258 flights	84.6% on time252 flights	88.7% on time225 flights	85.7% on time242 flights
8 AM–9 AM	106 flights, too few to score	104 flights, too few to score	104 flights, too few to score	103 flights, too few to score	105 flights, too few to score	65 flights, too few to score	106 flights, too few to score
9 AM–10 AM	74 flights, too few to score	63 flights, too few to score	45 flights, too few to score	72 flights, too few to score	72 flights, too few to score	30 flights, too few to score	56 flights, too few to score
10 AM–11 AM	108 flights, too few to score	102 flights, too few to score	90 flights, too few to score	114 flights, too few to score	105 flights, too few to score	62 flights, too few to score	94 flights, too few to score
11 AM–12 PM	81.1% on time230 flights	89.7% on time234 flights	85.3% on time233 flights	83.4% on time226 flights	80.3% on time226 flights	85.0% on time229 flights	79.7% on time229 flights
12 PM–1 PM	82 flights, too few to score	80 flights, too few to score	78 flights, too few to score	85 flights, too few to score	83 flights, too few to score	59 flights, too few to score	78 flights, too few to score
1 PM–2 PM	83.2% on time221 flights	87.5% on time224 flights	86.5% on time223 flights	76.9% on time222 flights	79.7% on time223 flights	83.6% on time220 flights	78.5% on time230 flights
2 PM–3 PM	100 flights, too few to score	85 flights, too few to score	82 flights, too few to score	99 flights, too few to score	101 flights, too few to score	67 flights, too few to score	82 flights, too few to score
3 PM–4 PM	81.1% on time206 flights	86.4% on time200 flights	85.6% on time202 flights	81.4% on time206 flights	78.0% on time207 flights	86.9% on time157 flights	78.6% on time210 flights
4 PM–5 PM	108 flights, too few to score	99 flights, too few to score	102 flights, too few to score	109 flights, too few to score	97 flights, too few to score	83 flights, too few to score	114 flights, too few to score
5 PM–6 PM	85 flights, too few to score	85 flights, too few to score	84 flights, too few to score	87 flights, too few to score	71 flights, too few to score	90.8% on time134 flights	90 flights, too few to score
6 PM–7 PM	75.3% on time151 flights	82.3% on time131 flights	72.9% on time131 flights	73.6% on time142 flights	73.3% on time153 flights	91 flights, too few to score	70.4% on time143 flights
7 PM–8 PM	79.9% on time160 flights	83.6% on time159 flights	78.0% on time162 flights	65.0% on time161 flights	74.8% on time161 flights	77.3% on time120 flights	72.6% on time164 flights
8 PM–9 PM	115 flights, too few to score	61 flights, too few to score	68 flights, too few to score	114 flights, too few to score	72.0% on time121 flights	55 flights, too few to score	73.2% on time132 flights

By departure window

5–9 AM86.9%

9 AM–12 PM83.1%

12–3 PM81.3%

3–6 PM79.7%

6–9 PM75.2%

9 PM–5 AM—

By departure hour

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

Departure windows with fewer than 120 flights are not scored.

Why SAN → SEA runs late

July 2023 – July 2026

Late-arriving aircraft46.7%

the inbound aircraft was late, so this flight started late

The airline32.5%

crew, maintenance, boarding and fueling, all within the carrier’s control

Air traffic control18.0%

airspace and airport capacity, including weather-driven flow control

Weather2.5%

weather severe enough to stop this flight specifically

Security0.4%

screening or terminal security incidents

Share of the delay minutes US DOT attributed to each cause for SAN → SEA. Only delays of 15 minutes or more are attributed.

Late-arriving aircraft is the largest cause on SAN → SEA, at 46.7%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 86.9% of the time and 6–9 PM departures 75.2%.

How this route holds up in bad weather

July 2023 – July 2026

The harder-hit end is the one the flight leaves from, where a cancellation keeps it from departing at all. Bad weather cancels 3.5 times the normal rate at SAN against 1.9 times at SEA. Cancelled in bad weather against normal hours: SAN 3.5% against 1.0%, SEA 1.5% against 0.8%. Flights that did leave SAN in bad weather arrived on time 66.7% of the time, against 78.4% in normal hours.

Bad weather and normal hours at the airports

Scheduled departures, July 2023 – July 2026

Departures from SAN and SEA in hours of bad weather and in normal hours
Departures from	SAN	SEA
Cancelled in bad weather	3.5%	1.5%
Cancelled in normal hours	1.0%	0.8%
Arrived on time, bad weather	66.7%	75.4%
Arrived on time, normal hours	78.4%	79.3%
Departures in bad weather	19,707	43,416

Delta Air Lines (1.6% cancelled against 3.7% for the other carriers at SAN) cancelled fewer departures from SAN in bad weather than the other carriers there did in the same months. None of the route’s other carriers was clearly worse.

This route’s airlines in bad weather at SAN

All departures from SAN

Cancellation rates in bad weather at SAN for the airlines that fly SAN to SEA, against the other carriers at SAN in the same months
Airline	Bad-weather departures	Cancelled	Other carriers
Delta Air Lines	2,191	1.6%below the others	3.7%
Alaska Airlines	2,278	3.2%about level	3.6%

These are airport figures, not route figures: every scheduled departure from SAN and SEA, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from SAN on every route.

Weather source and limits. In full: SAN (airlines), SEA, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.

Airlines on this route

Carriers with at least 200 flights, by the airline that operated each one.

Airlines on this route
Carrier	Flights	On time	Cancelled	Median delay	Severe
Alaska Airlines	8,783	79.0%	1.69%	-4 min	5.5%
Delta Air Lines	5,297	86.3%	0.57%	-11 min	4.9%

Alaska Airlines flew 62.4% of the 14,080 flights listed. Alaska Airlines cancelled 1.69% of its flights here against 0.57% for Delta Air Lines.

Delta Air Lines arrived on time 7.3 percentage points more often than Alaska Airlines on this route.

Flights on this route

Flight numbers with at least 600 operations here and still on the schedule.

Flights on this route
Flight	Scheduled	Operations	On time
DL2530 Delta Air Lines	7:20 AM	785	88.2%
DL2533 Delta Air Lines	1:45 PM	763	82.7%
DL2508 Delta Air Lines	11:15 AM	760	87.2%
DL2613 Delta Air Lines	7:15 PM	601	81.0%

DL2530 (7:20 AM) arrived on time 88.2% of the time, 7.2 points more often than DL2613 (7:15 PM) at 81.0%.

Weekly and seasonal patterns

By day of week

Mon80.3%

Tue86.8%

Wed84.6%

Thu79.4%

Fri77.5%

Sat84.7%

Sun78.7%

Tuesday is historically the most reliable day and Friday the least, a gap of 9.3 percentage points.

By month

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

June is historically the weakest month and February the strongest, a spread of 11.5 percentage points.

Reliability over time

July 2023 – July 2026

24

25

26

Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 81.0% against 78.9% in the 12 months before — improving by 2.1 percentage points.

Data and methodology

Calculated by FlyerIntel from 14,319 SAN → SEA flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.

Full methodology · Data sources · Report a problem

Analysis last recomputed September 26, 2026

SAN airport SEA airport Return direction SEA → SAN

SAN→SEA

Right now

Route reliability

Why SAN → SEA flights are cancelled

Share of cancellations

What each reason means

When it goes wrong

Will your connection be tight enough?

Best time to fly

By day and hour

By departure window

By departure hour

Why SAN → SEA runs late

How this route holds up in bad weather

Bad weather and normal hours at the airports

This route’s airlines in bad weather at SAN

Airlines on this route

Flights on this route

Weekly and seasonal patterns

By day of week

By month

Reliability over time

Data and methodology