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UA643 flight status
Monday, 28 Sept 2026
Checking the live status
Loading the live status and our prediction for today.
THE INCOMING AIRCRAFT
Checking the incoming aircraft
The aircraft and the flight bringing it here come with the live status.
- Airline status
- Loading
- Usual departure
- 06:00
- Usual arrival
- 07:40
- Flight duration
- 1h 40m
- Airline
- United Airlines
THE INCOMING AIRCRAFT
Checking the incoming aircraft
The aircraft and the flight bringing it here come with the live status.
Your operating aircraft
- Airline
- United Airlines
Aircraft assignments can change before departure.
Times are local to each airport. UTC is shown when the airport time zone is unavailable.
DelayAhead gives early estimates. It isn't an official airline notice, so always check with your airline before you travel.
UA643 delay history
How we count: on time means leaving or reaching the gate less than 15 min late. With only a takeoff time, a departure is late from 35 min, as takeoff comes after taxiing. With only a landing time, 1 to 14 min late is unclear and not counted. Cancelled flights are not counted. History, not a prediction.
Recent UA643 flights
The last 7 flights in our records, Fri 18 Sept to Thu 24 Sept. Newest first.
| Date | Departure | Arrival |
|---|---|---|
| Thu 24 Sept | On time +4 min | On time -19 min |
| Wed 23 Sept | On time +3 min takeoff time | On time -27 min |
| Tue 22 Sept | On time -6 min | On time +11 min |
| Mon 21 Sept | On time +8 min takeoff time | On time -25 min |
| Sun 20 Sept | Late +40 min takeoff time | On time +8 min |
| Sat 19 Sept | On time +11 min takeoff time | On time -17 min |
| Fri 18 Sept | On time +8 min takeoff time | On time -20 min |
Longer-term history
14 departures and 14 arrivals we could verify, Fri 11 Sept to Thu 24 Sept (our flight records keep up to 180 days).
Departures
86% departed on time
12 of 14 left on time Average delay when late: 38 minArrivals
100% arrived on time
14 of 14 arrived on time No delays of 15 minutes or more in this sampleLast 30 days of departures: 86% departed on time, 14% were 15 to 60 min late and 0% over 60 min late. Based on 14 verified flights.
UA643 schedule
- Usual departure
- 06:00 local time in Las Vegas
- Usual arrival
- 07:40 local time in San Francisco
- Scheduled flight time
- 1h 40m
- Flew on
- Every day in the last four weeks of our records
Based on recent flights in our records. Schedules change, so check the date you fly.
UA643 airports
- Departure airport
- Harry Reid International Airport (LAS)Las Vegas
- Arrival airport
- San Francisco International Airport (SFO)San Francisco