Flight number record

UA 1556

United Airlines · Newark to San Juan

Route: EWR → SJU
Departs: 09:43
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s UA 1556, check with United Airlines.

UA 1556 lands a B, level with the national rate of 77.6%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 45 minutes on average. That is a workable record, not a spotless one. That rests on 365 flights, with a median arrival 6 minutes early.

On time

78.1%

Arrivals under 15 minutes late, of 360 completed flights

Avg delay

46 min

Across delayed arrivals only, not all flights

Cancelled

1.37%

National rate is 1.81%

1 hour+ late

4.7%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. The median arrival is 6 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.

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 09:44 (117 flights) and 09:46 (94 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 09:43154 flights42.2%
Departs 09:44117 flights32.1%
Departs 09:4694 flights25.8%

Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.

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 84.1%, and UA 1556 runs 6 points worse at 78.1%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

UA 1556 next to EWR to SJU

Every carrier on EWR to SJU combined arrived on time 70.7% of the time across 2,101 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 71.0% on time. Across its whole network United Airlines managed 79.0%, close to this flight's figure.

UA 1556 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
UA 1556	365	78.1%	46 min	1.37%	B
All United Airlines on EWR–SJU	1,113	71.0%	75 min	2.34%	C
All carriers on EWR–SJU	2,101	70.7%	82 min	2.95%	C
United Airlines, whole network	821,041	79.0%	72 min	1.01%	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 91 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 202592 flights81.5%
Oct–Dec 202592 flights63.0%
Jan–Mar 202690 flights75.3%
Apr–Jun 202691 flights92.3%

Scale runs 55% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, UA 1556 did best on Sunday at 86.3% on time and worst on Thursday at 67.3%. Each day rests on about 52 flights, so a gap of 19 points is worth noticing but could still narrow in another year.

Delay causes

Why UA 1556 runs late

One category carries most of the weight here. National Airspace System accounts for 49% of the 3,638 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

National Airspace System
49%
Carrier
37%
Late-arriving aircraft
11%
Extreme weather
3%

The largest share of delay minutes, 37%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 1,340 of the 3,638 delay minutes reported here. The split is drawn from 3,638 delay minutes reported on UA 1556.

Cancellations sit at 1.37% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 4.7% land an hour or more behind schedule, against 8.1% 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 1,608 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 78.1% on time with 1.37% cancelled over 365 flights. Those are rates from the past twelve months, not a forecast for any particular day.

Where to go next

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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures