Airport month record
SFOAUG
San Francisco International in August 2026
- Departures
- 13,560
- Month
- August 2026
- National, same month
- 73.1%
- Carriers
- 8
Historical statistics for August 2026, not live status or a forecast for this year’s August. For today’s conditions at SFO, see live FAA status.
SFO in August draws a C+. About one flight in three arrives at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 13,560 flights, of which American Airlines flew 1,105 at 70.6% on time.
American Airlines is the most reliable of the eight carriers covered here at 70.6% on time across 1,105 flights.
Key figures
On time
65.5%
Arrivals under 15 minutes late, of 13,396 completed departures
Avg delay
64 min
Across delayed arrivals only, not all flights
Cancelled
0.73%
Nationally in August: 1.86%
Whole year
75.3%
SFO across all twelve months
These figures cover 13,560 departures from San Francisco International in August 2026. 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 10 points worse than the twelve-month rate of 75.3%, which makes it the worst of the twelve months in the data.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| 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+ |
| July 2026 | 13,841 | 66.1% | 66 min | 1.15% | C |
| August 2026 (this page) | 13,560 | 65.5% | 64 min | 0.73% | 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 44 points, against 31 points between the best and worst carrier.
- 5am–8am1,514 flights92.8%
- 8am–11am3,292 flights71.6%
- 11am–2pm2,081 flights48.6%
- 2pm–5pm2,532 flights51.5%
- 5pm–8pm1,677 flights61.6%
- 8pm–5am2,464 flights71.7%
Scale runs 40% to 100%.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 48.6% on time against 92.8% 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 3,292 flights scheduled in it.
Across the week, Tuesday is the strongest day at 76.8% on time and Thursday the weakest at 57.1%, a spread of 20 points.
Carrier by carrier
Which airlines ran best at SFO in August
The choice of carrier is not cosmetic here. American Airlines arrives on time 70.6% of the time; Southwest Airlines manages 39.8%. Sample sizes sit next to every figure, because a two-point gap across 1,003 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 5,670 | 70.5% | 56 min | 0.41% | C+ |
| SkyWest Airlines | 2,602 | 64.7% | 65 min | 0.31% | D+ |
| Delta Air Lines | 1,275 | 67.0% | 65 min | 0.55% | C+ |
| American Airlines | 1,105 | 70.6% | 93 min | 0.90% | C+ |
| Alaska Airlines | 1,069 | 62.2% | 60 min | 1.78% | D |
| Southwest Airlines | 1,003 | 39.8% | 63 min | 0.40% | F+ |
| JetBlue Airways | 450 | 68.7% | 63 min | 4.22% | C− |
| Frontier Airlines | 386 | 48.7% | 87 min | 2.33% | F |
JetBlue Airways cancels 4.2% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Route by route
Busiest routes out of SFO in August
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SFO to LAX · Los Angeles | 1,130 | 57.7% | 54 min | 0.35% | D+ |
| SFO to SAN · San Diego | 695 | 42.3% | 60 min | 0.58% | F+ |
| SFO to SEA · Seattle | 644 | 62.2% | 51 min | 0.93% | D+ |
| SFO to JFK · New York | 620 | 63.9% | 82 min | 3.87% | D− |
| SFO to ORD · Chicago | 556 | 66.2% | 90 min | 0.18% | C+ |
| SFO to LAS · Las Vegas | 543 | 53.4% | 66 min | 0.74% | F+ |
| SFO to BOS · Boston | 513 | 70.4% | 61 min | 1.75% | C |
| SFO to DEN · Denver | 485 | 63.9% | 76 min | 0.82% | D+ |
| SFO to DFW · Dallas-Fort Worth | 419 | 73.1% | 69 min | 0.72% | C+ |
| SFO to SNA · Santa Ana | 409 | 66.3% | 63 min | 1.96% | C |
| SFO to PHX · Phoenix | 378 | 64.1% | 72 min | 0.26% | D+ |
| SFO to EWR · Newarkthin sample | 361 | 67.0% | 70 min | 1.94% | C |
| SFO to PDX · Portlandthin sample | 325 | 68.2% | 56 min | 0.31% | C+ |
| SFO to ATL · Atlantathin sample | 292 | 77.9% | 69 min | 0.34% | B+ |
| SFO to IAH · Houstonthin sample | 279 | 74.7% | 39 min | 0.00% | C+ |
| SFO to BUR · Burbankthin sample | 276 | 67.8% | 57 min | 0.00% | C+ |
| SFO to SLC · Salt Lake Citythin sample | 272 | 63.5% | 62 min | 0.37% | D+ |
| SFO to AUS · Austinthin sample | 234 | 57.7% | 68 min | 0.00% | D+ |
| SFO to IAD · Washingtonthin sample | 214 | 68.9% | 49 min | 0.47% | C+ |
| SFO to HNL · Honoluluthin sample | 213 | 72.1% | 67 min | 2.35% | C |
| SFO to PHL · Philadelphiathin sample | 205 | 78.3% | 78 min | 0.00% | B+ |
| SFO to MSP · Minneapolisthin sample | 194 | 72.7% | 49 min | 0.00% | C+ |
| SFO to PSP · Palm Springsthin sample | 192 | 56.2% | 67 min | 0.00% | D+ |
| SFO to RNO · Renothin sample | 172 | 62.6% | 53 min | 0.00% | D+ |
| SFO to DTW · Detroitthin sample | 156 | 68.6% | 57 min | 0.00% | C+ |
Delay causes
What held SFO up in August
Late-arriving aircraft accounts for 45% of the 295,000 delay minutes carriers reported here, and the remaining four split what is left.
- 45%Late-arriving aircraft
- 30%National Airspace System
- 23%Carrier
- 2%Extreme weather
- 0%Security
45% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 295,000 reported delay minutes here, that single category outweighs weather by 26 to one. The split is drawn from 294,631 reported delay minutes.
Cancellations are rare at 0.73%, below the national 1.86% 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.
11.7% of arrivals land a full hour or more behind schedule, against 10.9% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
What to do with this
Flying from SFO in August
For a August trip through SFO: plan on this being one of the airport's harder months. The 5am–8am departures held up best at 92.8% on time, and with 11.7% of arrivals an hour or more late, a connection here deserves more slack than the same trip in March would.
Related
Where to go next
- San Francisco International (SFO), the whole year
- 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%
- SFO in July66.1%
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.