Route reliability record
KOA→SFO
Kailua-Kona to San Francisco
- Flights
- 1,079
- Period
- July 2025 to June 2026
- Distance
- 2,368 mi
- Carriers
- 2
This route lands a B+, 6 points better than the national rate of 77.6%. About one flight in six 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 1,079 KOA to SFO flights, with a median arrival 9 minutes early.
Best time to fly KOA to SFO: a 5am–8am departure, ideally on a Monday. Flights in that window arrived on time 100.0% of the time and Monday flights 85.8%, against 83.4% for the route overall.
Set against the rest of the country, this route's record is 6 points better than the US average of 77.6%. That gap is worth roughly 58 fewer late arrivals for every thousand flights.
Key figures
On time
83.4%
Arrivals under 15 minutes late, of 1,066 completed flights
Avg delay
65 min
Across delayed arrivals only, not all flights
Cancelled
0.93%
National rate is 1.81%
Best carrier
United
86.5% on time across 861 flights
These figures cover 1,079 flights between July 2025 and June 2026. The median arrival is 9 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
Which airline is most reliable on KOA to SFO
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 |
|---|---|---|---|---|---|
| United Airlines | 861 | 86.5% | 67 min | 1.05% | A |
| Alaska Airlinesthin sample | 218 | 71.4% | 61 min | 0.46% | C+ |
Flight by flight
Flights on KOA to SFO
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 22 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am41 flights100.0%
- 8am–11am1 flights—
- 11am–2pm284 flights78.5%
- 2pm–5pm409 flights78.5%
- 5pm–8pm46 flights80.4%
- 8pm–5am298 flights92.9%
Scale runs 70% to 100%. 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 78.5% on time against 100.0% 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 2pm–5pm window is the busiest, with 409 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 22 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
September is the best month on the calendar at 93.5% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. June was the busiest month here, with 146 flights.
Across the week, Monday is the strongest day at 85.8% on time and Thursday the weakest at 77.6%. 8 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Late-arriving aircraft accounts for 47% of the 11,000 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.
- 47%Late-arriving aircraft
- 35%Carrier
- 18%National Airspace System
- 0%Extreme weather
47% 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 11,000 reported delay minutes here, that single category outweighs weather by 47 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 11,464 reported delay minutes.
The largest share of delay minutes, 35%, 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 4,023 of the 11,000 delay minutes reported here.
Cancellations sit at 0.93% against a national 1.81%, which is ordinary. Diversions add another 0.28%.
Connections and stage length
What a delay here actually costs
Badly late arrivals are rare here: only 4.9% 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 86.3% on time across 1,080 flights, within 3 points 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. 1,079 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.
Work out the risk of missing a connection in SFO after this flight
What to do with this
Booking this route
Put together: treat all of this as provisional. 1,079 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 83.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 1,066 completed flights over 12 months sit behind that.
Common questions
KOA to SFO questions
How often is KOA to SFO delayed?
About one flight in six arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 16.6% of the 1,079 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.
How reliable is KOA to SFO compared with the rest of the country?
83.4% of flights arrive on time here against a national 77.6%, a difference of 6 points in its favour. That is worth a B+ on this site's grading scale.
What time of day has the fewest delays on KOA to SFO?
The 5am–8am departure window is the strongest at 100.0% on time. The 2pm–5pm window is the weakest at 78.5%, 22 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are October delays on KOA to SFO?
October is the weakest month at 71.2% on time, compared with 93.5% in September. Across the year that is 22 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- SFO to KOA — the return legseparate record
- San Francisco International (SFO) delay statistics
- United Airlines on KOA to SFO86.5%
- Alaska Airlines on KOA to SFO71.4%
- KOA to HNL, a related route85.1%
- LAX to SFO, a related route64.8%
- KOA to LAX, a related route86.8%
- United Airlines on-time record86.5%
- Alaska Airlines on-time record71.4%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Direction matters. KOA to SFO and SFO to KOA are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed KOA to SFO’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
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.