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Route · SEA → SJC · 2020–2025 BTS data

Seattle to San Jose

According to PlainFlights' route traffic ranking (BTS On-Time Performance total flights), SEA to SJC (Seattle to San Jose) ranks #185 of 4927 tracked domestic routes by total flights (most flights = #1).

Data updated 2026-06-13

85%
On-time
+6 pts
vs US avg
57 min
Delay when late
26,361
Flights
#185 of 4927
Corpus placement

Cancelled

0.9%

Best Month

Jan 2025 91%

Worst Month

Jul 2025 73%

Distance

696 mi

Carriers

19

Monthly Performance

Recent 24 months of route data.

Period Flights Delayed Cancelled Diverted Carriers
Dec 2025 353 78 3 0 WN,AS,OO
Nov 2025 374 56 2 0 OO,AS,WN
Oct 2025 392 60 4 0 AS,OO,WN
Sep 2025 367 62 0 0 WN,OO,AS
Aug 2025 395 83 3 0 OO,WN,AS
Jul 2025 425 115 10 0 AS,OO,WN
Jun 2025 412 96 6 0 AS,OO,WN
May 2025 387 72 2 0 AS,OO,WN
Apr 2025 345 53 0 0 OO,WN,AS
Mar 2025 349 64 2 0 AS,OO,WN
Feb 2025 317 64 7 0 AS,OO,WN
Jan 2025 353 32 3 1 AS,OO,WN
Dec 2024 346 68 0 0 AS,OO,WN
Nov 2024 352 51 0 0 OO,WN,AS
Oct 2024 405 78 2 0 AS,OO,WN
Sep 2024 423 81 5 0 WN,OO,AS
Aug 2024 432 108 4 0 AS,WN,OO
Jul 2024 431 82 3 0 AS,OO,WN
Jun 2024 407 105 1 0 AS,DL,OO,WN
May 2024 379 72 0 0 AS,DL,OO,WN
Apr 2024 358 56 1 0 AS,DL,OO,WN
Mar 2024 366 55 1 0 AS,OO,WN
Feb 2024 307 47 3 1 AS,OO,WN
Jan 2024 317 61 19 0 AS,WN,OO

SEA–SJC seasonal on-time pattern

Best: March (87.9%) · weakest: December (80.3%)

78%80%82%84%86%88%90% JanFebMarAprMayJunJulAugSepOctNovDec 80.3%

Strongest calendar month

March

87.9% on-time · ~386 flights/mo

Busiest calendar month

July

~398 flights/mo avg

Weakest calendar month

December

80.3% on-time · ~333 flights/mo

Cancellation Rate

0.9%

81 of 8,992 flights

Diversion Rate

0.0%

2 of 8,992 flights

Explore origin & destination

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

SEA - Seattle

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

SEA on-time profile

SJC - San Jose

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

SJC on-time profile

Compare the two airports

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

Compare SEA vs SJC

Origin-hub reliability standing

Among SEA's stronger departures

SEA → SJC posts a 85% on-time rate, landing in the ≥85% band with 25 of 89 BTS-tracked routes leaving Seattle. The same hub also shows 63 mid-band and 1 challenged departures · fleet-wide on-time rank #1235 of 4927 (highest on-time = #1).

What the Data Says About SEA to SJC

Seattle to San Jose (SEA to SJC) is one of the more dependable pairings in the BTS On-Time Performance dataset: a 85% on-time rate across 26,361 flights, with delays that do happen averaging 56.7 minutes. The corridor runs roughly 696 miles and is served by 19 carriers. Over the most recent 24 months, 81 of 8,992 flights were cancelled (0.9%) and 2 diverted (0.0%).

The monthly split is wide on this route: Jan 2025 posted the strongest performance at 91% on-time, while Jul 2025 came in at just 73% - a 18-point swing worth factoring into travel timing.

On the multi-year calendar, SEA–SJC peaks in March at 87.9% on-time while July carries the heaviest traffic (~398 flights per month) ; the softest month is December at 80.3%, a 7.6-point swing that repeats because the corridor's weather and holiday mix stays stable year to year.

Frequently Asked Questions

Where does SEA to SJC rank among US routes by traffic? ▼
According to PlainFlights' route traffic ranking, SEA to SJC ranks #185 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 SEA to SJC? ▼
Flights from Seattle to San Jose have a 85% on-time rate based on 26,361 flights. The average delay is 56.7 minutes. The best recent month was Jan 2025 with 91% on-time.
What is the cancellation rate for SEA to SJC? ▼
Over the last 24 months, 0.9% of flights on this route were cancelled (81 of 8,992 flights) and 0.0% were diverted.
How far is the flight from SEA to SJC? ▼
The flight distance from Seattle (SEA) to San Jose (SJC) is approximately 696 miles. This route is served by 19 carriers.
When is the best time to fly from SEA to SJC? ▼
The best recent month for on-time performance was Jan 2025 (91% on-time). The worst was Jul 2025 (73% on-time). Consider booking during months with historically better performance.

Airports on this route

SEA Airport

Seattle
SJC Airport

San Jose
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 SEA–SJC data

SEA–SJC runs 6 pts above the national 79% average; the remaining risk is month-to-month swing and carrier mix, not a weak headline rate.

  • Compare SEA and SJC airport profiles: delay causes and top routes differ even on the same corridor. SEA airport
  • If your dates flex, March (87.9% on-time) beats December (80.3%) on this corridor. Seasonal chart
  • 4 other routes post a similar 85% 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.