Flight number record
UA 1556
United Airlines · Newark to San Juan
- Route
- EWR → SJU
- Departs
- 09:43
- Flights
- 365
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s UA 1556, check with United Airlines.
UA 1556 lands a B, level with the national rate of 77.3%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by about 50 minutes on average. That rests on 365 flights, with a median arrival 5 minutes early.
Key figures
On time
76.9%
Arrivals under 15 minutes late, of 360 completed flights
Avg delay
50 min
Across delayed arrivals only, not all flights
Cancelled
1.37%
National rate is 1.89%
1 hour+ late
5.8%
National rate is 8.3%
These figures cover 365 flights between September 2025 and August 2026. The median arrival is 5 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
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Schedule
When UA 1556 flies
UA 1556 flies EWR to SJU without a single fixed slot. Its most common scheduled departure was 09:43, used on 154 of 365 flights, with 09:46 (135 flights) and 09:44 (55 flights) next.
- Departs 09:43154 flights42.2%
- Departs 09:46135 flights37.0%
- Departs 09:4455 flights15.1%
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 09:43 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 83.9%, and UA 1556 runs 7 points worse at 76.9%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
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Against the route
UA 1556 next to EWR to SJU
Every carrier on EWR to SJU combined arrived on time 69.9% of the time across 2,078 flights, so UA 1556 is 7 points ahead of it. United flew 1,113 flights on the same city pair under all its flight numbers, including this one, and those ran 69.7% on time. Across its whole network United Airlines managed 78.8%, which this flight trails by 2 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| UA 1556 | 365 | 76.9% | 50 min | 1.37% | B |
| All United Airlines on EWR–SJU | 1,113 | 69.7% | 80 min | 2.16% | C |
| All carriers on EWR–SJU | 2,078 | 69.9% | 81 min | 3.03% | C− |
| United Airlines, whole network | 830,825 | 78.8% | 73 min | 1.02% | B |
Across the year
UA 1556 quarter by quarter
UA 1556 did not run the same all year. Its best quarter was Apr–Jun 2026 at 92.3% on time and its weakest Oct–Dec 2025 at 63.0%, a swing of 29 points on roughly 73 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 flights86.7%
- Oct–Dec 202592 flights63.0%
- Jan–Mar 202690 flights75.3%
- Apr–Jun 202691 flights92.3%
- Jul–Sep 202662 flights72.6%
Scale runs 55% to 100%.
By weekday, UA 1556 did best on Tuesday at 84.3% on time and worst on Thursday at 71.2%. Each day rests on about 52 flights, so a gap of 13 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late UA 1556 runs when it is late
The 83 late arrivals split 32 under half an hour, 30 between 30 and 60 minutes, and 21 an hour or more.
- 15+ min early82 flights22.8%
- Within 15 min195 flights54.2%
- 15–29 min late32 flights8.9%
- 30–59 min late30 flights8.3%
- 1–2 hours late15 flights4.2%
- 2+ hours late6 flights1.7%
Scale runs 0% to 100%.
Share of 360 completed flights by arrival against schedule.
10 of 46 late departures made up the time and arrived on time, 22% of them. In the other direction, 47 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 SJU.
The worst days
Worst days for UA 1556
The latest arrival of the period was on 14 December 2025, 3 hours 46 minutes behind schedule; most of its delay minutes were filed as extreme weather. On three of the five worst days the largest share was filed as carrier-caused (crew, maintenance, fuelling, baggage).
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 14 December 2025 | 3 hours 46 minutes | Extreme weather |
| 6 July 2026 | 3 hours 18 minutes | Carrier |
| 4 July 2026 | 2 hours 49 minutes | National Airspace System |
| 13 October 2025 | 2 hours 27 minutes | Carrier |
| 26 August 2026 | 2 hours 15 minutes | Carrier |
Delay causes
Why UA 1556 runs late
National Airspace System accounts for 51% of the 4,120 delay minutes carriers reported here, and the remaining four split what is left.
- 51%National Airspace System
- 37%Carrier
- 8%Late-arriving aircraft
- 3%Extreme weather
The largest share of delay minutes, 37%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1,540 of the 4,120 delay minutes reported here. The split is drawn from 4,120 delay minutes reported on UA 1556.
Cancellations sit at 1.37% against a national 1.89%, which is ordinary. Diversions add another 0.00%.
Connections and routes
What a delay on this flight costs
5.8% 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.
At 1,608 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.
Every one of the 365 flights under UA 1556 in the data flew EWR to SJU. The number was not reused on any other city pair, which makes this a clean record of one route.
One caution: this is a thin sample. 365 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 1556
For a booking, read UA 1556 as 76.9% on time with 1.37% cancelled over 365 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- EWR to SJU, every carrier and departure
- SJU to EWR, the return direction
- United Airlines 2143 on the same route67.1%
- United Airlines 1543 on the same route64.2%
- Newark Liberty International (EWR) delay statistics
- Luis Munoz Marin International (SJU) 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.