Flight number record
UA 1723
United Airlines · San Francisco to Kailua-Kona
- Route
- SFO → KOA
- Departs
- 16:55
- Flights
- 278
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s UA 1723, check with United Airlines.
UA 1723 lands a B+, 2 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 35 minutes on average. That rests on 278 flights, with a median arrival 2 minutes early.
Key figures
On time
79.7%
Arrivals under 15 minutes late, of 276 completed flights
Avg delay
34 min
Across delayed arrivals only, not all flights
Cancelled
0.72%
National rate is 1.89%
1 hour+ late
2.5%
National rate is 8.3%
These figures cover 278 flights between September 2025 and August 2026. The median arrival is 2 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.
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Schedule
When UA 1723 flies
UA 1723 flies SFO to KOA without a single fixed slot. Its most common scheduled departure was 16:55, used on 203 of 278 flights.
- Departs 16:55203 flights73.0%
Scale runs 0% to 100%.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 16:55 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 71.9%, and UA 1723 runs 8 points better at 79.7%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
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Against the route
UA 1723 next to SFO to KOA
Every carrier on SFO to KOA combined arrived on time 86.9% of the time across 1,202 flights, so UA 1723 is 7 points behind it. United flew 958 flights on the same city pair under all its flight numbers, including this one, and those ran 85.7% on time. Across its whole network United Airlines managed 78.8%, close to this flight's figure.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 1723thin sample | 278 | 79.7% | 34 min | 0.72% | B+ |
| All United Airlines on SFO–KOA | 958 | 85.7% | 50 min | 0.52% | A+ |
| All carriers on SFO–KOA | 1,202 | 86.9% | 51 min | 0.42% | A+ |
| United Airlines, whole network | 830,825 | 78.8% | 73 min | 1.02% | B |
Across the year
UA 1723 quarter by quarter
Quarter by quarter UA 1723 held fairly steady: 83.3% in Jul–Sep 2025, 79.1% in Oct–Dec 2025, 78.4% in Jan–Mar 2026, 83.5% in Apr–Jun 2026 and 73.8% in Jul–Sep 2026. A spread of 10 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.
- Jul–Sep 202530 flights83.3%
- Oct–Dec 202543 flights79.1%
- Jan–Mar 202652 flights78.4%
- Apr–Jun 202691 flights83.5%
- Jul–Sep 202662 flights73.8%
Scale runs 65% to 90%.
By weekday, UA 1723 did best on Saturday at 89.7% on time and worst on Wednesday at 68.4%. Each day rests on about 40 flights, so a gap of 21 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late UA 1723 runs when it is late
Most of the lateness is short. 31 of the 56 late arrivals were under half an hour behind, and 7 reached an hour or more. Not one arrived two hours late.
- 15+ min early59 flights21.4%
- Within 15 min161 flights58.3%
- 15–29 min late31 flights11.2%
- 30–59 min late18 flights6.5%
- 1–2 hours late7 flights2.5%
- 2+ hours late0 flights0.0%
Scale runs 0% to 100%.
Share of 276 completed flights by arrival against schedule.
A late pushback is often recovered here: of 52 departures that left 15 minutes late or more, 22 still arrived on time. In the other direction, 26 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at KOA.
The worst days
Worst days for UA 1723
The latest arrival of the period was on 31 August 2026, 1 hour 43 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The five worst days are spread across August, April, June and October, with no single month standing out.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 31 August 2026 | 1 hour 43 minutes | Carrier |
| 20 April 2026 | 1 hour 20 minutes | Late-arriving aircraft |
| 10 June 2026 | 1 hour 14 minutes | Late-arriving aircraft |
| 14 October 2025 | 1 hour 9 minutes | Carrier |
| 21 August 2026 | 1 hour 9 minutes | National Airspace System |
Delay causes
Why UA 1723 runs late
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 1,887 reported delay minutes.
- 36%National Airspace System
- 33%Carrier
- 31%Late-arriving aircraft
36% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 682 minutes out of 1,887, against a national NAS share of 21%. The split is drawn from 1,887 delay minutes reported on UA 1723.
Cancellations are rare at 0.72%, below the national 1.89% 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 routes
What a delay on this flight costs
Badly late arrivals are rare here: only 2.5% land an hour or more behind schedule, against 8.3% 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 same number turns up on eight other city pairs in the data, including IDA to DEN (36), IAH to ATL (15) and PHX to ORD (6), but none flew often enough under UA 1723 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SFO to KOA only.
One caution: this is a thin sample. 278 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 UA 1723
For a booking, UA 1723 is one of the weaker ways to fly SFO to KOA: 7 points below the route as a whole. If the schedule allows, compare it with the other departures listed on the route page before settling on this one.
Related
Where to go next
- SFO to KOA, every carrier and departure
- KOA to SFO, the return direction
- United Airlines 1721 on the same route87.8%
- San Francisco International (SFO) delay statistics
- United Airlines on-time record
- Every United Airlines flight number with a record
- The most and least reliable flight numbers in the US
- Worst months to fly in the US, ranked by the data
A flight number here means United Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.
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.