United Airlines
Is UA521 delayed?
No delay reported yet. UA521 is scheduled to leave Atlanta at 16:17 on Nov 14 and reach Houston at 17:08 (as of Nov 14, 16:13 UTC).
Usually on time: arrived within 15 min of schedule on 34 of the last 43 flights.
Each route and date is shown separately. Confirm that both airports match your booking.
No live update yet
Showing the published schedule until live times come in.
Update time unavailable
Departure
Atlanta
ATL
Scheduled
Nov 14
Arrival
Houston
IAH
Scheduled
Nov 14
Times shown in airport local time
Service date: · Scheduled departure date (America/New_York)
Flight details
Departure · UTC
- Scheduled
- Estimated
- Not available
- Actual
- Not available
Arrival · UTC
- Scheduled
- Estimated
- Not available
- Actual
- Not available
No live update yet
Showing the published schedule until live times come in.
Update time unavailable
Departure
Houston
IAH
Scheduled
Nov 14
Arrival
Boston
BOS
Scheduled
Nov 14
Times shown in airport local time
Service date: · Scheduled departure date (America/Chicago)
Flight details
Departure · UTC
- Scheduled
- Estimated
- Not available
- Actual
- Not available
Arrival · UTC
- Scheduled
- Estimated
- Not available
- Actual
- Not available
Recent arrivals
Dates below are arrival dates in the destination airport’s time zone. The detailed history uses service dates.
- 39 min late
Houston → Boston
- On schedule (1 min behind)
Atlanta → Houston
- 18 min early
Houston → Boston
- 9 min early
Atlanta → Houston
- 19 min early
Houston → Boston
Is UA521 usually late?
Period: Oct 15, 2026 – Nov 14, 2026
On time means arriving no more than 15 minutes after the scheduled time; late means more than 15 minutes after. Cancelled and diverted flights are counted apart from arrivals. Compares scheduled and actual arrival times. Cancelled and diverted flights are left out. Some flights may be missing.
At the airports today
Atlanta (ATL) departures
- Left more than 15 min late
- 71 of 123
- Cancelled today
- 98
Houston (IAH) departures
- Left more than 15 min late
- 18 of 56
- Cancelled today
- 53
Related flights
Flight history and details
| Service date | Departure | Arrival | Actual | Arrival delay (minutes) |
|---|---|---|---|---|
| Nov 13, 2026Cancelled | Houston | Boston | Not available | Not available |
| Nov 13, 2026Cancelled | Atlanta | Houston | Not available | Not available |
| Nov 12, 2026Arrived | Houston | Boston | 39 | |
| Nov 12, 2026Arrived | Atlanta | Houston | 1 | |
| Nov 11, 2026Arrived | Houston | Boston | -18 | |
| Nov 11, 2026Arrived | Atlanta | Houston | -9 | |
| Nov 10, 2026Arrived | Houston | Boston | -19 | |
| Nov 9, 2026Arrived | Houston | Boston | -17 | |
| Nov 9, 2026Arrived | Atlanta | Houston | 14 | |
| Nov 8, 2026Arrived | Houston | Boston | -11 | |
| Nov 8, 2026Arrived | Atlanta | Houston | -1 | |
| Nov 7, 2026Arrived | Houston | Boston | 14 | |
| Nov 7, 2026Arrived | Atlanta | Houston | 4 | |
| Nov 6, 2026Arrived | Houston | Boston | -11 | |
| Nov 6, 2026Arrived | Atlanta | Houston | 3 | |
| Nov 5, 2026Arrived | Houston | Boston | -36 | |
| Nov 5, 2026Arrived | Atlanta | Houston | 128 | |
| Nov 4, 2026Arrived | Houston | Boston | -25 | |
| Nov 4, 2026Arrived | Atlanta | Houston | 226 | |
| Nov 3, 2026Arrived | Houston | Boston | 1 | |
| Nov 2, 2026Arrived | Houston | Boston | 73 | |
| Nov 1, 2026Arrived | Houston | Boston | 1 | |
| Nov 1, 2026Arrived | Atlanta | Houston | -12 | |
| Oct 31, 2026Arrived | Houston | Boston | -7 | |
| Oct 30, 2026Arrived | Houston | Boston | -2 | |
| Oct 30, 2026Arrived | Atlanta | Houston | -6 | |
| Oct 29, 2026Arrived | Houston | Boston | -17 | |
| Oct 29, 2026Arrived | Atlanta | Houston | -3 | |
| Oct 28, 2026Arrived | Houston | Boston | -6 | |
| Oct 28, 2026Arrived | Atlanta | Houston | -10 | |
| Oct 27, 2026Arrived | Houston | Boston | 30 | |
| Oct 26, 2026Arrived | Houston | Boston | 154 | |
| Oct 26, 2026Arrived | Atlanta | Houston | 22 | |
| Oct 25, 2026Arrived | Houston | Boston | 8 | |
| Oct 25, 2026Arrived | Atlanta | Houston | -2 | |
| Oct 24, 2026Arrived | Houston | Orlando | -15 | |
| Oct 23, 2026Arrived | Houston | Boston | 1 | |
| Oct 22, 2026Arrived | Houston | Boston | 16 | |
| Oct 21, 2026Arrived | Houston | Boston | -18 | |
| Oct 20, 2026Arrived | Houston | Boston | -1 | |
| Oct 19, 2026Arrived | Houston | Boston | 5 | |
| Oct 18, 2026Arrived | Houston | Boston | -10 | |
| Oct 17, 2026Arrived | Houston | Orlando | 3 | |
| Oct 16, 2026Arrived | Houston | Boston | 29 | |
| Oct 15, 2026Arrived | Houston | Boston | -32 |