Airport month record

SJCDEC

Norman Y. Mineta San Jose International in December 2025

Departures: 3,622
Month: December 2025
National, same month: 73.2%
Carriers: 8

Historical statistics for December 2025, not live status or a forecast for this year’s December. For today’s conditions at SJC, see live FAA status.

SJC in December lands a B+, 8 points better than the national rate of 73.2%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 3,622 flights, of which SkyWest Airlines flew 673 at 83.0% on time.

Set against the rest of the country, SJC's December record is 8 points better than the US average of 73.2%. That gap is worth roughly 80 fewer late arrivals for every thousand flights.

On time

81.2%

Arrivals under 15 minutes late, of 3,581 completed departures

Avg delay

58 min

Across delayed arrivals only, not all flights

Cancelled

0.86%

Nationally in December: 1.55%

Whole year

82.9%

SJC across all twelve months

These figures cover 3,622 departures from Norman Y. Mineta San Jose International in December 2025. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.

Against the year

December next to SJC's other months

Against SJC's own year, December ran 2 points worse than the twelve-month rate of 82.9%, which makes it number ten of twelve months, best first. Either side of it, November ran 83.0% on time and January 89.3%, so a trip moved by a few weeks would have landed in a better stretch.

SJC month by month
Month	Flights	On time	Avg delay	Cancelled	Grade
July 2025	4,120	80.8%	60 min	0.87%	B+
August 2025	3,885	83.5%	54 min	0.36%	B+
September 2025	3,777	85.5%	51 min	0.50%	A+
October 2025	3,865	81.5%	52 min	0.41%	B+
November 2025	3,659	83.0%	57 min	1.12%	B
December 2025 (this page)	3,622	81.2%	58 min	0.86%	B+
January 2026	3,099	89.3%	61 min	1.19%	A
February 2026	3,088	87.0%	51 min	0.58%	A+
March 2026	3,438	85.6%	59 min	0.96%	A+
April 2026	3,423	84.2%	45 min	0.50%	B+
May 2026	3,686	81.7%	48 min	0.38%	B+
June 2026	3,816	74.3%	50 min	0.58%	C+

Departure window

The best time of day to leave SJC in December

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 20 points, against 5 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am786 flights92.3%
8am–11am742 flights84.8%
11am–2pm592 flights81.5%
2pm–5pm674 flights74.4%
5pm–8pm574 flights72.3%
8pm–5am254 flights73.9%

Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 92.3% of the time, against 72.3% for the evening window. That is 20 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 786 flights scheduled in it.

Across the week, Thursday is the strongest day at 86.5% on time and Friday the weakest at 71.8%. 15 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at SJC in December

The two carriers here are closely matched: 5 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.

Carriers at SJC in December 2025
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines	2,214	78.2%	49 min	0.63%	B+
SkyWest Airlines	673	83.0%	77 min	1.04%	B
Alaska Airlinesthin sample	201	87.8%	65 min	1.99%	A
Delta Air Linesthin sample	181	91.4%	94 min	2.76%	A
American Airlinesthin sample	140	83.6%	93 min	0.00%	B+
United Airlinesthin sample	93	91.3%	55 min	0.00%	A+
Hawaiian Airlinesthin sample	62	93.5%	211 min	0.00%	A+
Envoy Airthin sample	39	87.2%	43 min	0.00%	A+

No carrier stands out. SkyWest tops the table at 83.0%, 5 points clear of the bottom, which is inside the range this kind of sample moves year to year.

Route by route

Busiest routes out of SJC in December

Routes from SJC in December 2025
Route	Flights	On time	Avg delay	Cancelled	Grade
SJC to SAN · San Diego	396	64.9%	54 min	1.77%	D
SJC to LAX · Los Angeles	379	82.1%	82 min	1.32%	B
SJC to SEA · Seattlethin sample	354	79.7%	61 min	1.13%	B
SJC to LAS · Las Vegasthin sample	320	80.6%	50 min	0.00%	B+
SJC to PHX · Phoenixthin sample	276	81.5%	44 min	0.00%	B+
SJC to SNA · Santa Anathin sample	229	78.1%	50 min	0.87%	B+
SJC to DEN · Denverthin sample	217	83.7%	53 min	0.00%	B+
SJC to BUR · Burbankthin sample	184	84.8%	55 min	2.72%	B
SJC to PDX · Portlandthin sample	184	87.0%	47 min	0.00%	A+
SJC to SLC · Salt Lake Citythin sample	137	93.3%	69 min	1.46%	A
SJC to ONT · Ontariothin sample	118	84.7%	34 min	0.00%	B+
SJC to AUS · Austinthin sample	93	75.0%	42 min	1.08%	B
SJC to LGB · Long Beachthin sample	93	80.4%	59 min	1.08%	B
SJC to DFW · Dallas-Fort Worththin sample	91	80.2%	101 min	0.00%	B+
SJC to ATL · Atlantathin sample	88	91.8%	38 min	2.27%	A
SJC to HNL · Honoluluthin sample	73	88.9%	129 min	0.00%	A+
SJC to BOI · Boisethin sample	71	85.9%	56 min	0.00%	A+
SJC to OGG · Kahuluithin sample	42	92.9%	31 min	0.00%	A+
SJC to BNA · Nashvillethin sample	31	83.9%	69 min	0.00%	B+
SJC to HOU · Houstonthin sample	31	96.7%	19 min	3.23%	A−
SJC to MDW · Chicagothin sample	31	96.8%	18 min	0.00%	A+
SJC to DAL · Dallasthin sample	31	96.8%	22 min	0.00%	A+
SJC to RNO · Renothin sample	31	93.5%	27 min	0.00%	A+
SJC to MSP · Minneapolisthin sample	31	80.0%	151 min	3.23%	B−

Delay causes

What held SJC up in December

One category carries most of the weight here. Late-arriving aircraft accounts for 47% of the 39,000 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.

Late-arriving aircraft
47%
Carrier
33%
National Airspace System
17%
Extreme weather
3%
Security
0%

47% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 39,000 reported delay minutes here, that single category outweighs weather by 15 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 39,218 reported delay minutes.

Cancellations are rare at 0.86%, below the national 1.55% 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.

5.7% of arrivals land an hour or more late, close to the national 10.0%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.

What to do with this

Flying from SJC in December

For a December trip through SJC: plan on this being one of the airport's harder months. The 5am–8am departures held up best at 92.3% on time, and with 5.7% of arrivals an hour or more late, a connection here deserves more slack than the same trip in January would.

Norman Y. Mineta San Jose International (SJC), the whole year
SJC in July80.8%
SJC in August83.5%
SJC in September85.5%
SJC in October81.5%
SJC in November83.0%
SJC in January89.3%
SJC in February87.0%
SJC in March85.6%
SJC in April84.2%
SJC in May81.7%
SJC in June74.3%

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