Airport month record
SFOMAY
San Francisco International in May 2026
- Departures
- 13,114
- Month
- May 2026
- National, same month
- 78.6%
- Carriers
- 8
Historical statistics for May 2026, not live status or a forecast for this year’s May. For today’s conditions at SFO, see live FAA status.
SFO in May sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 9 points worse than the national rate of 78.6%. The late ones land about an hour behind schedule. That rests on 13,114 flights, of which JetBlue Airways flew 388 at 78.3% on time.
JetBlue Airways is the most reliable of the seven carriers covered here at 78.3% on time across 388 flights.
Key figures
On time
70.1%
Arrivals under 15 minutes late, of 12,974 completed departures
Avg delay
64 min
Across delayed arrivals only, not all flights
Cancelled
0.79%
Nationally in May: 0.92%
Whole year
75.3%
SFO across all twelve months
These figures cover 13,114 departures from San Francisco International in May 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
May next to SFO's other months
Against SFO's own year, May ran 5 points worse than the twelve-month rate of 75.3%, which makes it number nine of twelve months, best first. Either side of it, April ran 74.7% on time and June 67.1%, so this month sits in line with its neighbours.
| 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 (this page) | 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 | 13,560 | 65.5% | 64 min | 0.73% | C+ |
Departure window
The best time of day to leave SFO in May
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 41 points, against 34 points between the best and worst carrier.
- 5am–8am1,524 flights94.1%
- 8am–11am2,979 flights75.0%
- 11am–2pm2,084 flights53.1%
- 2pm–5pm2,235 flights61.5%
- 5pm–8pm1,678 flights69.4%
- 8pm–5am2,614 flights71.6%
Scale runs 45% to 100%.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 53.1% on time against 94.1% 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 2,979 flights scheduled in it.
Across the week, Saturday is the strongest day at 82.2% on time and Thursday the weakest at 61.2%, a spread of 21 points.
Carrier by carrier
Which airlines ran best at SFO in May
The choice of carrier is not cosmetic here. JetBlue Airways arrives on time 78.3% of the time; Southwest Airlines manages 44.4%. Sample sizes sit next to every figure, because a two-point gap across 858 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 5,657 | 76.1% | 55 min | 0.28% | B+ |
| SkyWest Airlines | 2,518 | 65.9% | 70 min | 1.35% | C |
| Delta Air Lines | 1,235 | 68.4% | 62 min | 1.30% | C |
| American Airlines | 1,087 | 72.3% | 90 min | 1.47% | C |
| Alaska Airlines | 1,010 | 68.8% | 48 min | 0.69% | C+ |
| Southwest Airlines | 858 | 44.4% | 70 min | 0.93% | F+ |
| JetBlue Airways | 388 | 78.3% | 59 min | 0.00% | B+ |
| Frontier Airlinesthin sample | 361 | 58.2% | 79 min | 1.66% | D |
The spread between JetBlue and Southwest is 34 points, wide enough that it should decide the booking. On a hundred trips that is 34 more arrivals inside the on-time window.
Route by route
Busiest routes out of SFO in May
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SFO to LAX · Los Angeles | 1,028 | 65.3% | 60 min | 1.46% | C |
| SFO to SEA · Seattle | 594 | 62.1% | 51 min | 0.84% | D+ |
| SFO to JFK · New York | 593 | 75.7% | 73 min | 0.67% | B+ |
| SFO to ORD · Chicago | 559 | 73.2% | 81 min | 0.18% | C+ |
| SFO to LAS · Las Vegas | 535 | 60.8% | 75 min | 0.56% | D+ |
| SFO to SAN · San Diego | 529 | 55.9% | 64 min | 1.13% | D |
| SFO to DEN · Denver | 483 | 71.5% | 54 min | 0.00% | C+ |
| SFO to BOS · Boston | 439 | 75.4% | 58 min | 0.00% | B+ |
| SFO to PHX · Phoenix | 417 | 68.5% | 85 min | 0.24% | C+ |
| SFO to EWR · Newark | 404 | 82.7% | 67 min | 0.99% | B+ |
| SFO to DFW · Dallas-Fort Worth | 400 | 67.6% | 59 min | 3.50% | C− |
| SFO to SNA · Santa Ana | 400 | 65.6% | 49 min | 2.00% | C |
| SFO to IAH · Houstonthin sample | 307 | 78.8% | 44 min | 0.00% | B+ |
| SFO to SLC · Salt Lake Citythin sample | 306 | 65.7% | 54 min | 0.98% | C+ |
| SFO to PDX · Portlandthin sample | 299 | 67.9% | 56 min | 0.00% | C+ |
| SFO to BUR · Burbankthin sample | 289 | 63.4% | 58 min | 1.73% | D |
| SFO to ATL · Atlantathin sample | 285 | 73.2% | 62 min | 0.35% | C+ |
| SFO to IAD · Washingtonthin sample | 268 | 83.2% | 65 min | 0.00% | B+ |
| SFO to AUS · Austinthin sample | 253 | 62.7% | 74 min | 0.40% | D+ |
| SFO to HNL · Honoluluthin sample | 215 | 75.2% | 55 min | 0.47% | B+ |
| SFO to PSP · Palm Springsthin sample | 213 | 61.0% | 86 min | 1.41% | D |
| SFO to PHL · Philadelphiathin sample | 210 | 80.3% | 61 min | 0.95% | B+ |
| SFO to RNO · Renothin sample | 170 | 64.9% | 67 min | 1.18% | D |
| SFO to MSP · Minneapolisthin sample | 168 | 74.5% | 50 min | 1.19% | C |
| SFO to MIA · Miamithin sample | 164 | 69.3% | 46 min | 0.00% | C+ |
Delay causes
What held SFO up in May
Late-arriving aircraft accounts for 52% of the 248,000 delay minutes carriers reported here, and the remaining four split what is left.
- 52%Late-arriving aircraft
- 24%Carrier
- 23%National Airspace System
- 1%Extreme weather
- 0%Security
52% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 248,000 reported delay minutes here, that single category outweighs weather by 46 to one. The split is drawn from 247,941 reported delay minutes.
Cancellations are rare at 0.79%, below the national 0.92% 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.
9.9% of arrivals land a full hour or more behind schedule, against 7.1% 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 May
For a May trip through SFO: expect 70.1% on time and 0.79% cancelled, going by May 2026. The 5am–8am window was the strongest part of the day.
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 June67.1%
- SFO in July66.1%
- SFO in August65.5%
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.