May 2026 · US Department of Transportation filings
Los Angeles (LAX) to San Francisco (SFO) on United Airlines
United Airlines flew 604 flights between Los Angeles (LAX) and San Francisco (SFO) in May 2026. On the worse direction, 52% arrived more than 15 minutes late. These are the airline's own filings to the federal government, not our estimates, and every figure below shows the number of flights behind it.
Both directions, measured separately
Los Angeles (LAX) to San Francisco (SFO)
- Arrived over 15 min late
- 52%of 302 flights
- Cancelled
- 0%
- Average delay
- 31min
Of every filed minute of delay on United Airlines flights Los Angeles (LAX) to San Francisco (SFO), 18.3% was coded as carrier delay or late-arriving aircraft and 0% as extreme weather. The commitments US airlines make to rebook you and cover meals turn on whether a delay was within their control, which is why the split is worth reading — though which side your own flight fell on is not something a monthly total can answer.
- Carrier delay — 4.9%
Filed against the carrier's own operation — crew, maintenance, fuelling, baggage. - Late-arriving aircraft — 13.4%
Filed because the inbound aircraft was late. What delayed it is not recorded. - Air traffic system — 81.7%
Volume, routing and airport capacity, attributed to the national airspace system.
That first figure is two filed categories added together: carrier delay, and late-arriving aircraft. BTS reports them separately and the sum is ours. It is not a finding of fault — the late-arriving code records that the inbound aircraft was late, not what delayed it, so some of it began as weather or traffic flow earlier in the day. Both components are listed above so you can reject the sum.
These are monthly aggregate filing codes. They cannot establish what caused your individual flight, whether it was within the carrier's control, or whether compensation is owed.
San Francisco (SFO) to Los Angeles (LAX)
- Arrived over 15 min late
- 26.5%of 302 flights
- Cancelled
- 0%
- Average delay
- 14.3min
Of every filed minute of delay on United Airlines flights San Francisco (SFO) to Los Angeles (LAX), 90.9% was coded as carrier delay or late-arriving aircraft and 0% as extreme weather. The commitments US airlines make to rebook you and cover meals turn on whether a delay was within their control, which is why the split is worth reading — though which side your own flight fell on is not something a monthly total can answer.
- Carrier delay — 21.1%
Filed against the carrier's own operation — crew, maintenance, fuelling, baggage. - Late-arriving aircraft — 69.8%
Filed because the inbound aircraft was late. What delayed it is not recorded. - Air traffic system — 9.1%
Volume, routing and airport capacity, attributed to the national airspace system.
That first figure is two filed categories added together: carrier delay, and late-arriving aircraft. BTS reports them separately and the sum is ours. It is not a finding of fault — the late-arriving code records that the inbound aircraft was late, not what delayed it, so some of it began as weather or traffic flow earlier in the day. Both components are listed above so you can reject the sum.
These are monthly aggregate filing codes. They cannot establish what caused your individual flight, whether it was within the carrier's control, or whether compensation is owed.
Figures cover May 2026, a single reporting month, from the US DOT Bureau of Transportation Statistics On-Time Performance database. Retrieved 2026-07-28. Reporting under 14 CFR part 234 covers domestic US scheduled service only, so no international route appears — including anything to or from Mexico.
What you are owed when it does run late
Both airports are in the United States or a US territory, so this is a domestic itinerary and the significant-delay threshold is 3 hours. A 3-hour delay meets it.
- Full refund of the fare, taxes and ancillary fees — Owed under § 260.6(a) — but only if you decline what the airline offers instead. Accepting a rebooking, voucher or travel credit ends the refund right. If you want your money back, say no to the alternative.
- Paid back to your original form of payment — § 260.2 defines a prompt refund as 7 business days for a card purchase and 20 calendar days for anything else. Where you have refused a voucher, the airline cannot substitute one for cash.
- No cash compensation on top of the refund — Unlike EU 261, US law requires no compensation for the disruption itself. Meals and hotels come from the carrier's own customer service plan under 14 CFR 259.5, so they differ by airline — worth asking for, but not a statutory right.
How to read these numbers
“Late” means arriving more than 15 minutes after the scheduled gate time, which is the threshold the Department of Transportation uses. Cause shares describe delay minutes, not flights, so a small number of very long delays can dominate them. We publish a route only when it carries at least 300 flights in the window, because below that a couple of bad days produces a dramatic percentage that means nothing.
Reporting under 14 CFR part 234 covers domestic US service by the larger US carriers, so these pages cover neither international routes nor Mexican airlines.