Airport month record

SFOAUG

San Francisco International in August 2025

Departures: 12,594
Month: August 2025
National, same month: 77.4%
Carriers: 9

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

SFO in August lands a B+, 2 points better than the national rate of 77.4%. 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 12,594 flights, of which JetBlue Airways flew 380 at 87.8% on time.

JetBlue Airways is the most reliable of the seven carriers covered here at 87.8% on time across 380 flights.

On time

79.6%

Arrivals under 15 minutes late, of 12,470 completed departures

Avg delay

66 min

Across delayed arrivals only, not all flights

Cancelled

0.64%

Nationally in August: 1.08%

Whole year

77.3%

SFO across all twelve months

These figures cover 12,594 departures from San Francisco International in August 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

August next to SFO's other months

Against SFO's own year, August ran 2 points better than the twelve-month rate of 77.3%, which makes it number six of twelve months, best first. Either side of it, July ran 73.9% on time and September 82.4%, so this month sits in line with its neighbours.

SFO month by month
Month	Flights	On time	Avg delay	Cancelled	Grade
July 2025	12,958	73.9%	67 min	1.14%	C
August 2025 (this page)	12,594	79.6%	66 min	0.64%	B+
September 2025	11,830	82.4%	58 min	0.25%	B+
October 2025	12,774	80.1%	61 min	0.36%	B+
November 2025	12,022	78.6%	66 min	1.86%	B
December 2025	11,975	76.3%	81 min	1.07%	B
January 2026	11,113	82.5%	85 min	2.43%	B
February 2026	10,316	81.7%	77 min	1.21%	B
March 2026	12,171	84.0%	72 min	1.02%	B
April 2026	12,401	74.7%	63 min	0.70%	C+
May 2026	13,114	70.1%	64 min	0.79%	C+
June 2026	13,415	67.1%	67 min	0.70%	C+

Departure window

The best time of day to leave SFO in August

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 14 points, against 23 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am1,676 flights89.9%
8am–11am2,838 flights81.1%
11am–2pm2,223 flights76.0%
2pm–5pm2,047 flights76.6%
5pm–8pm1,306 flights80.4%
8pm–5am2,504 flights76.3%

Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.

The weak window here is the middle of the day, not the evening: 11am–2pm runs 76.0% on time against 89.9% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 8am–11am window is the busiest, with 2,838 flights scheduled in it.

Across the week, Tuesday is the strongest day at 84.5% on time and Sunday the weakest at 74.9%. 10 points is a smaller lever than departure hour, but it is free.

Carrier by carrier

Which airlines ran best at SFO in August

The choice of carrier is not cosmetic here. JetBlue Airways arrives on time 87.8% of the time; Southwest Airlines manages 65.0%. Sample sizes sit next to every figure, because a two-point gap across 749 flights means less than a ten-point one.

Carriers at SFO in August 2025
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	5,087	80.8%	63 min	0.86%	B+
SkyWest Airlines	2,758	82.8%	63 min	0.18%	B+
Delta Air Lines	1,204	83.9%	70 min	0.58%	B+
American Airlines	1,068	76.9%	95 min	1.03%	B
Alaska Airlines	964	74.6%	58 min	0.62%	C+
Southwest Airlines	749	65.0%	50 min	0.00%	C+
JetBlue Airways	380	87.8%	78 min	0.26%	A+
Frontier Airlinesthin sample	299	63.0%	81 min	2.34%	D
Hawaiian Airlinesthin sample	85	83.3%	44 min	0.00%	B+

The spread between JetBlue and Southwest is 23 points, wide enough that it should decide the booking. On a hundred trips that is 23 more arrivals inside the on-time window.

Route by route

Busiest routes out of SFO in August

Routes from SFO in August 2025
Route	Flights	On time	Avg delay	Cancelled	Grade
SFO to LAX · Los Angeles	928	77.8%	63 min	0.65%	B+
SFO to SEA · Seattle	620	71.4%	60 min	0.65%	C+
SFO to SAN · San Diego	593	68.4%	60 min	0.17%	C+
SFO to JFK · New York	591	84.2%	93 min	0.85%	B+
SFO to ORD · Chicago	523	76.0%	77 min	2.68%	B
SFO to LAS · Las Vegas	521	82.1%	64 min	0.19%	B+
SFO to DEN · Denver	460	71.1%	54 min	0.22%	C+
SFO to BOS · Boston	431	84.8%	67 min	0.23%	B+
SFO to SNA · Santa Ana	424	85.5%	54 min	0.47%	A+
SFO to EWR · Newark	384	69.0%	83 min	2.86%	C
SFO to PHX · Phoenixthin sample	341	78.6%	64 min	0.88%	B+
SFO to DFW · Dallas-Fort Worththin sample	337	70.4%	88 min	1.78%	C
SFO to PDX · Portlandthin sample	327	85.5%	53 min	0.61%	A+
SFO to ATL · Atlantathin sample	304	79.5%	63 min	0.33%	B+
SFO to IAH · Houstonthin sample	299	79.1%	52 min	0.33%	B+
SFO to SLC · Salt Lake Citythin sample	294	83.6%	63 min	0.34%	B+
SFO to IAD · Washingtonthin sample	254	79.7%	66 min	1.18%	B
SFO to AUS · Austinthin sample	250	84.1%	40 min	0.80%	B+
SFO to BUR · Burbankthin sample	237	81.9%	63 min	0.00%	B+
SFO to HNL · Honoluluthin sample	202	83.0%	90 min	0.50%	B+
SFO to MSP · Minneapolisthin sample	180	87.2%	65 min	0.56%	A+
SFO to PHL · Philadelphiathin sample	167	77.8%	71 min	0.00%	B+
SFO to PSP · Palm Springsthin sample	162	80.9%	62 min	0.00%	B+
SFO to DTW · Detroitthin sample	159	82.3%	52 min	0.63%	B+
SFO to OGG · Kahuluithin sample	145	91.0%	31 min	0.00%	A+

Delay causes

What held SFO up in August

One category carries most of the weight here. Late-arriving aircraft accounts for 42% of the 167,000 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
42%
Carrier
37%
National Airspace System
19%
Extreme weather
2%
Security
0%

42% 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 167,000 reported delay minutes here, that single category outweighs weather by 20 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 167,271 reported delay minutes.

Cancellations are rare at 0.64%, below the national 1.08% 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.

6.4% of arrivals land an hour or more late, close to the national 8.2%. 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 SFO in August

For a August trip through SFO: expect 79.6% on time and 0.64% cancelled, going by August 2025. The 5am–8am window was the strongest part of the day.

San Francisco International (SFO), the whole year
SFO in July73.9%
SFO in September82.4%
SFO in October80.1%
SFO in November78.6%
SFO in December76.3%
SFO in January82.5%
SFO in February81.7%
SFO in March84.0%
SFO in April74.7%
SFO in May70.1%
SFO in June67.1%

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