Carrier route record
UASFO→KOA
United Airlines · San Francisco to Kailua-Kona
- Flights
- 862
- Period
- July 2025 to June 2026
- Share of route
- 80%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on SFO to KOA earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs about 50 minutes. That rests on 862 flights, with a median arrival 8 minutes early.
Set against the rest of the country, United's SFO to KOA record is 8 points better than the US average of 77.6%. That gap is worth roughly 78 fewer late arrivals for every thousand flights.
Key figures
On time
85.4%
Arrivals under 15 minutes late, of 856 completed flights
Avg delay
50 min
Across delayed arrivals only, not all flights
Cancelled
0.35%
National rate is 1.81%
Whole route
86.3%
Every carrier on SFO to KOA, 1,080 flights
These figures cover 862 flights between July 2025 and June 2026. The median arrival is 8 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
United against every carrier on SFO to KOA
United flew 862 of the 1,080 flights on SFO to KOA, most of the route. Its 85.4% on time is about level with the route as a whole at 86.3%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from Alaska at 89.9% to United at 85.4%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Alaska Airlinesthin sample | 218 | 89.9% | 62 min | 0.00% | A+ |
| United Airlines (this page) | 862 | 85.4% | 50 min | 0.35% | A+ |
Flight by flight
United flight numbers on SFO to KOA
Departure window
When United runs best on this route
Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 862 flights.
- 5am–8am20 flights—
- 8am–11am469 flights87.8%
- 11am–2pm52 flights84.3%
- 2pm–5pm28 flights—
- 5pm–8pm293 flights80.8%
- 8pm–5am—
Scale runs 70% to 95%. Rows with fewer than 30 flights show a dash.
The early departures do better, though not dramatically: 87.8% on time for the 8am–11am window against 80.8% for 5pm–8pm. Worth taking if the schedule allows, not worth an extra connection. The 8am–11am window is the busiest, with 469 flights scheduled in it.
Across the year
United on SFO to KOA through the year
August is the worst month at 75.4% on time, 19 points below January, the best at 94.4%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. June was the busiest month here, with 120 flights.
Across the week, Monday is the strongest day at 89.3% on time and Wednesday the weakest at 78.4%. 11 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 50% of the 6,298 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.
- 50%Late-arriving aircraft
- 34%Carrier
- 16%National Airspace System
50% 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 6,298 reported delay minutes here, that single category outweighs weather by 50 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 6,298 reported delay minutes.
The largest share of delay minutes, 34%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 2,145 of the 6,298 delay minutes reported here.
Cancellations are rare at 0.35%, below the national 1.81% 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.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 4.4% land an hour or more behind schedule, against 8.1% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
At 2,368 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
The return leg runs 86.5% on time across 861 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 862 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking United on SFO to KOA
Put together: treat all of this as provisional. 862 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 85.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 856 completed flights over 12 months sit behind that.
Related
Where to go next
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.