Flight number record
UA 406
United Airlines · San Francisco to Las Vegas
- Route
- SFO → LAS
- Departs
- 21:15
- Flights
- 340
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s UA 406, check with United Airlines.
UA 406 lands a B+, about a point worse than the national rate of 77.3%. About one flight in four arrives 15 minutes late or worse, and those flights are late by about 50 minutes on average. That rests on 340 flights, with a median arrival 5 minutes early.
Key figures
On time
76.3%
Arrivals under 15 minutes late, of 338 completed flights
Avg delay
51 min
Across delayed arrivals only, not all flights
Cancelled
0.59%
National rate is 1.89%
1 hour+ late
8.3%
National rate is 8.3%
These figures cover 340 flights between September 2025 and August 2026. Beyond the headline rate, 8.3% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Schedule
When UA 406 flies
UA 406 flies SFO to LAS without a single fixed slot. Its most common scheduled departure was 21:15, used on 80 of 340 flights, with 21:00 (78 flights) and 20:45 (52 flights) next.
- Departs 21:1580 flights23.5%
- Departs 21:0078 flights22.9%
- Departs 20:4552 flights15.3%
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 21:15 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.1%, and UA 406 runs 6 points better at 76.3%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Against the route
UA 406 next to SFO to LAS
Every carrier on SFO to LAS combined arrived on time 70.2% of the time across 6,140 flights, so UA 406 is 6 points ahead of it. United flew 2,817 flights on the same city pair under all its flight numbers, including this one, and those ran 76.8% on time. Across its whole network United Airlines managed 78.8%, which this flight trails by 3 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 406thin sample | 340 | 76.3% | 51 min | 0.59% | B+ |
| All United Airlines on SFO–LAS | 2,817 | 76.8% | 55 min | 0.35% | B+ |
| All carriers on SFO–LAS | 6,140 | 70.2% | 65 min | 0.70% | C+ |
| United Airlines, whole network | 830,825 | 78.8% | 73 min | 1.02% | B |
Across the year
UA 406 quarter by quarter
UA 406 did not run the same all year. Its best quarter was Jan–Mar 2026 at 89.7% on time and its weakest Apr–Jun 2026 at 66.3%, a swing of 23 points on roughly 68 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
- Jul–Sep 202530 flights83.3%
- Oct–Dec 202575 flights69.3%
- Jan–Mar 202687 flights89.7%
- Apr–Jun 202687 flights66.3%
- Jul–Sep 202661 flights76.7%
Scale runs 60% to 95%.
By weekday, UA 406 did best on Tuesday at 85.7% on time and worst on Thursday at 63.3%. Each day rests on about 49 flights, so a gap of 22 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late UA 406 runs when it is late
UA 406 often beats the schedule: 91 of 338 completed flights, 27%, arrived 15 minutes or more early. The 80 late arrivals split 27 under half an hour, 25 between 30 and 60 minutes, and 28 an hour or more.
- 15+ min early91 flights26.9%
- Within 15 min167 flights49.4%
- 15–29 min late27 flights8.0%
- 30–59 min late25 flights7.4%
- 1–2 hours late26 flights7.7%
- 2+ hours late2 flights0.6%
Scale runs 0% to 100%.
Share of 338 completed flights by arrival against schedule.
A late pushback is often recovered here: of 90 departures that left 15 minutes late or more, 27 still arrived on time. In the other direction, 17 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 LAS.
The worst days
Worst days for UA 406
The latest arrival of the period was on 9 November 2025, 3 hours 1 minute behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). On three of the five worst days the largest share was filed as a late-arriving aircraft.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 9 November 2025 | 3 hours 1 minute | Carrier |
| 19 June 2026 | 2 hours 9 minutes | Late-arriving aircraft |
| 28 May 2026 | 1 hour 56 minutes | Late-arriving aircraft |
| 21 May 2026 | 1 hour 52 minutes | Late-arriving aircraft |
| 1 January 2026 | 1 hour 49 minutes | National Airspace System |
Delay causes
Why UA 406 runs late
Late-arriving aircraft accounts for 45% of the 4,071 delay minutes carriers reported here, and the remaining four split what is left.
- 45%Late-arriving aircraft
- 32%National Airspace System
- 23%Carrier
45% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 4,071 reported delay minutes here, that single category outweighs weather by 45 to one. The split is drawn from 4,071 delay minutes reported on UA 406.
Cancellations are rare at 0.59%, 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
8.3% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about 50 minutes, which a normal layover absorbs.
UA 406 is not only a SFO to LAS flight. It also flew LAS to EWR (319 flights, 83.4% on time) often enough to be scored on its own. Airlines attach one number to several legs of an aircraft's day, and each leg keeps its own record here, so check which city pair is on your booking before reading a rate.
One caution: this is a thin sample. 340 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.
| Also flown as | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| LAS to EWRthin sample | 319 | 83.4% | 65 min | 2.82% | B |
What to do with this
Booking UA 406
For a booking, read UA 406 as 76.3% on time with 0.59% cancelled over 340 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- SFO to LAS, every carrier and departure
- LAS to SFO, the return direction
- United Airlines 1995 on the same route79.4%
- United Airlines 751 on the same route68.8%
- Alaska Airlines 776 on the same route59.2%
- United Airlines 611 on the same route76.1%
- Alaska Airlines 718 on the same route87.5%
- Frontier Airlines 4158 on the same route60.9%
- San Francisco International (SFO) delay statistics
- Harry Reid International (LAS) 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
- Why the first flight of the morning is statistically safest
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.