Likely delayed: there are delays at UA 2040's airports as of 6:47 PM ET. It arrived on time 53.4% of the time in June-August 2026. When it was late, the average delay was 1h 47m. 1.9% of flights were cancelled. SFO has major delays (wind, max 5 hours and 41 minutes), so this flight is likely to be delayed.
Looks on time
Leg 2 of 3 (BOS → ORD): Should be in the air from BOS, scheduled to land at ORD at 7:00 PM local time.
Cancellation risk: Medium 1.9% of its flights were cancelled in June-August 2026; SFO has major delays.
Estimate from the schedule, live position and airport conditions, if this flight operates today. Check United for official times.
Before you fly
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Route and schedule
| Leg | Scheduled | On time |
|---|---|---|
| SAN → EWR San Diego, CA to Newark, NJ | 6:35 AM → 3:06 PM | 100% |
| BOS → ORD Boston, MA to Chicago, IL | 5:00 PM → 7:00 PM | 50% |
| ORD → SFO Chicago, IL to San Francisco, CA | 9:28 PM → 12:16 AM | 71% |
Local times. Schedules change; check your booking.
How reliable is UA 2040?
| Arrived on time (within 15 min) | 53.4% |
| Average delay when late | 107 min |
| Cancelled | 1.9% |
| Diverted | 0% |
| Flights tracked | 105 |
Best and worst days to fly UA 2040
UA 2040 was most reliable on Thursdays (67% on time) and least reliable on Fridays (38%).
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Why it runs late
| Late-arriving plane | |
| Airline (crew, maintenance) | |
| Air traffic system | |
| Extreme weather |
Share of delay minutes by cause, as reported by United to the Department of Transportation.
Other flights BOS → ORD
All flights on this route, ranked
Live status at its airports
We show airport-wide airport status, not this flight's gate or live position. For that, check the United app.
United delays and what you're owed · Airline phone numbers
About this data
On-time history: U.S. Bureau of Transportation Statistics, Reporting Carrier On-Time Performance, June-August 2026. Live conditions: live airport status. "On time" means arriving within 15 minutes of schedule.
Common questions
Is UA 2040 delayed today?
SFO has major delays (wind, max 5 hours and 41 minutes), so this flight is likely to be delayed. Checked 6:47 PM ET. For this flight's gate and exact status, check the United app.
Is UA 2040 usually on time?
UA 2040 arrived within 15 minutes of schedule 53.4% of the time in June-August 2026, with an average delay of 107 minutes when late.
How often is UA 2040 cancelled?
1.9% of UA 2040 flights were cancelled in June-August 2026.