Flight number record
UA 1387
United Airlines · San Francisco to Houston
- Route
- SFO → IAH
- Departs
- 12:15
- Flights
- 288
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s UA 1387, check with United Airlines.
UA 1387 sits in the middle of the pack with a B+. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.3%. The late ones land roughly 45 minutes behind schedule. That rests on 288 flights, with a median arrival 1 minute late.
Key figures
On time
75.4%
Arrivals under 15 minutes late, of 285 completed flights
Avg delay
46 min
Across delayed arrivals only, not all flights
Cancelled
0.35%
National rate is 1.89%
1 hour+ late
4.6%
National rate is 8.3%
These figures cover 288 flights between September 2025 and August 2026. On-time means an arrival less than 15 minutes after the scheduled gate time, the same threshold the Department of Transportation uses in its own reports. Cancelled and diverted flights are excluded from the on-time rate and counted separately, which is why the cancellation column matters on its own.
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Schedule
When UA 1387 flies
UA 1387 flies SFO to IAH without a single fixed slot. Its most common scheduled departure was 12:15, used on 82 of 288 flights, with 12:35 (50 flights) and 13:00 (50 flights) next.
- Departs 12:1582 flights28.5%
- Departs 12:3550 flights17.4%
- Departs 13:0050 flights17.4%
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 12:15 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.3%, and UA 1387 runs 3 points worse at 75.4%. 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 1387 next to SFO to IAH
Every carrier on SFO to IAH combined arrived on time 84.0% of the time across 3,578 flights, so UA 1387 is 9 points behind it. 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 1387thin sample | 288 | 75.4% | 46 min | 0.35% | B+ |
| All United Airlines on SFO–IAH | 3,578 | 84.0% | 50 min | 0.25% | B+ |
| All carriers on SFO–IAH | 3,578 | 84.0% | 50 min | 0.25% | B+ |
| United Airlines, whole network | 830,825 | 78.8% | 73 min | 1.02% | B |
Across the year
UA 1387 quarter by quarter
UA 1387 did not run the same all year. Its best quarter was Jan–Mar 2026 at 83.0% on time and its weakest Jul–Sep 2026 at 67.2%, a swing of 16 points on roughly 72 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 20256 flights—
- Oct–Dec 202576 flights74.3%
- Jan–Mar 202653 flights83.0%
- Apr–Jun 202691 flights76.9%
- Jul–Sep 202662 flights67.2%
Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.
By weekday, UA 1387 ranged from 71.4% on Sunday to 82.1% on Wednesday. With about 41 flights behind each day, a spread of 11 points is inside normal variation, so the day you fly is not worth changing for this flight.
Arrival by arrival
How late UA 1387 runs when it is late
The 70 late arrivals split 31 under half an hour, 26 between 30 and 60 minutes, and 13 an hour or more.
- 15+ min early43 flights15.1%
- Within 15 min172 flights60.4%
- 15–29 min late31 flights10.9%
- 30–59 min late26 flights9.1%
- 1–2 hours late7 flights2.5%
- 2+ hours late6 flights2.1%
Scale runs 0% to 100%.
Share of 285 completed flights by arrival against schedule.
13 of 53 late departures made up the time and arrived on time, 25% of them. In the other direction, 30 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 IAH.
The worst days
Worst days for UA 1387
The latest arrival of the period was on 16 March 2026, 3 hours 53 minutes behind schedule; most of its delay minutes were filed as national airspace system delay. The five worst days are spread across March, November, June and August, with no single month standing out.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 16 March 2026 | 3 hours 53 minutes | National Airspace System |
| 30 November 2025 | 2 hours 45 minutes | Late-arriving aircraft |
| 7 March 2026 | 2 hours 29 minutes | National Airspace System |
| 2 June 2026 | 2 hours 28 minutes | Carrier |
| 20 August 2026 | 2 hours 22 minutes | Carrier |
Delay causes
Why UA 1387 runs late
National Airspace System accounts for 46% of the 3,229 delay minutes carriers reported here, and the remaining four split what is left.
- 46%National Airspace System
- 31%Late-arriving aircraft
- 23%Carrier
46% 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 1,487 minutes out of 3,229, against a national NAS share of 21%. The split is drawn from 3,229 delay minutes reported on UA 1387.
Cancellations are rare at 0.35%, 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 4.6% 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 1,635 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 five other city pairs in the data, including PIT to SFO (77), ORD to SFO (55) and PHX to SFO (46), but none flew often enough under UA 1387 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SFO to IAH only.
One caution: this is a thin sample. 288 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 1387
For a booking, UA 1387 is one of the weaker ways to fly SFO to IAH: 9 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 IAH, every carrier and departure
- IAH to SFO, the return direction
- United Airlines 2305 on the same route80.8%
- United Airlines 505 on the same route82.2%
- San Francisco International (SFO) delay statistics
- George Bush Intercontinental (IAH) 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.