PlainFlights

Route · SJC → SEA · 2020–2025 BTS data

San Jose to Seattle

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), SJC to SEA (San Jose to Seattle) ranks #186 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

86.4%
On-time
+7.4 pts
vs US avg
61 min
Delay when late
26,343
Flights
#186 of 4927
Corpus placement

Cancelled

1.0%

Best Month

Jan 2025 93%

Worst Month

Jun 2024 74%

Distance

696 mi

Carriers

19

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 354 71 4 1 WN,AS,OO
Nov 2025 373 58 1 0 OO,AS,WN
Oct 2025 392 58 5 1 AS,OO,WN
Sep 2025 367 62 0 0 WN,OO,AS
Aug 2025 395 76 3 0 OO,WN,AS
Jul 2025 425 90 9 0 AS,OO,WN
Jun 2025 412 93 6 0 AS,OO,WN
May 2025 388 65 3 0 AS,OO,WN
Apr 2025 345 49 0 0 OO,WN,AS
Mar 2025 350 48 2 2 AS,OO,WN
Feb 2025 317 40 7 0 AS,OO,WN
Jan 2025 354 26 2 2 AS,OO,WN
Dec 2024 346 49 1 2 AS,OO,WN
Nov 2024 351 45 2 0 OO,WN,AS
Oct 2024 406 40 1 0 AS,OO,WN
Sep 2024 424 90 6 1 WN,OO,AS
Aug 2024 430 88 4 0 AS,WN,OO
Jul 2024 431 84 3 0 AS,OO,WN
Jun 2024 408 106 1 0 AS,DL,OO,WN
May 2024 378 68 1 0 AS,DL,OO,WN
Apr 2024 359 48 2 0 AS,DL,OO,WN
Mar 2024 367 42 1 0 AS,OO,WN
Feb 2024 317 39 2 1 AS,OO,WN
Jan 2024 324 48 25 1 AS,WN,OO

SJC–SEA seasonal on-time pattern

Best: April (89.3%) · weakest: June (80.9%)

80%82%84%86%88%90% JanFebMarAprMayJunJulAugSepOctNovDec 84.4%

Strongest calendar month

April

89.3% on-time · ~343 flights/mo

Busiest calendar month

July

~398 flights/mo avg

Weakest calendar month

June

80.9% on-time · ~374 flights/mo

Cancellation Rate

1.0%

91 of 9,013 flights

Diversion Rate

0.1%

11 of 9,013 flights

Explore origin & destination

On-time and delay data for the airports this route connects.

SJC - San Jose

Full on-time, delay-cause, and seasonal performance for San Jose, CA.

SJC on-time profile

SEA - Seattle

Full on-time, delay-cause, and seasonal performance for Seattle, WA.

SEA on-time profile

Compare the two airports

See SJC and SEA side by side on delays, cancellations, and reliability.

Compare SJC vs SEA

Origin-hub reliability standing

Among SJC's stronger departures

SJC → SEA posts a 86.4% on-time rate, landing in the ≥85% band with 21 of 31 BTS-tracked routes leaving San Jose. The same hub also shows 9 mid-band and 1 challenged departures · fleet-wide on-time rank #805 of 4927 (highest on-time = #1).

What the Data Says About SJC to SEA

San Jose to Seattle (SJC to SEA) is one of the more dependable pairings in the BTS On-Time Performance dataset: a 86.4% on-time rate across 26,343 flights, with delays that do happen averaging 60.5 minutes. The corridor runs roughly 696 miles and is served by 19 carriers. Over the most recent 24 months, 91 of 9,013 flights were cancelled (1.0%) and 11 diverted (0.1%).

The monthly split is wide on this route: Jan 2025 posted the strongest performance at 93% on-time, while Jun 2024 came in at just 74% - a 19-point swing worth factoring into travel timing.

On the multi-year calendar, SJC–SEA peaks in April at 89.3% on-time while July carries the heaviest traffic (~398 flights per month) ; the softest month is June at 80.9%, a 8.4-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does SJC to SEA rank among US routes by traffic? ▼
According to PlainFlights' route traffic ranking, SJC to SEA ranks #186 of 4927 tracked domestic routes by total flights (most flights = #1). That ordinal matches our busiest-routes listing (total_flights DESC). See /methodology#corpus-placement for the exact sort basis.
How often are flights delayed from SJC to SEA? ▼
Flights from San Jose to Seattle have a 86.4% on-time rate based on 26,343 flights. The average delay is 60.5 minutes. The best recent month was Jan 2025 with 93% on-time.
What is the cancellation rate for SJC to SEA? ▼
Over the last 24 months, 1.0% of flights on this route were cancelled (91 of 9,013 flights) and 0.1% were diverted.
How far is the flight from SJC to SEA? ▼
The flight distance from San Jose (SJC) to Seattle (SEA) is approximately 696 miles. This route is served by 19 carriers.
When is the best time to fly from SJC to SEA? ▼
The best recent month for on-time performance was Jan 2025 (93% on-time). The worst was Jun 2024 (74% on-time). Consider booking during months with historically better performance.

Airports on this route

SJC Airport

San Jose
SEA Airport

Seattle
Data source

Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.

Read our methodology - how this data is sourced, computed, and verified.

Using SJC–SEA data

SJC–SEA runs 7.4 pts above the national 79% average; the remaining risk is month-to-month swing and carrier mix, not a weak headline rate.

  • Compare SJC and SEA airport profiles: delay causes and top routes differ even on the same corridor. SJC airport
  • If your dates flex, April (89.3% on-time) beats June (80.9%) on this corridor. Seasonal chart
  • 4 other routes post a similar 86.4% on-time rate; compare before you commit to this pairing. Similar routes

On-time rate reflects the BTS historical average across all reporting carriers on this origin–destination pair, not any single flight or booking recommendation.

Data sourced from U.S. Department of Transportation Bureau of Transportation Statistics (BTS) On-Time Performance data. See our methodology for details. Retrieved and formatted by PlainFlights

Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.