Flight number record

UA 1833

United Airlines · Boston to Newark

Route: BOS → EWR
Departs: 06:00
Flights: 330
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s UA 1833, check with United Airlines.

UA 1833 earns an A−. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 17 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 330 flights, with a median arrival 14 minutes early.

Set against the rest of the country, UA 1833's record is 17 points better than the US average of 77.6%. That gap is worth roughly 168 fewer late arrivals for every thousand flights.

On time

94.4%

Arrivals under 15 minutes late, of 320 completed flights

Avg delay

66 min

Across delayed arrivals only, not all flights

Cancelled

3.03%

National rate is 1.81%

1 hour+ late

1.9%

National rate is 8.1%

These figures cover 330 flights between July 2025 and June 2026. The median arrival is 14 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 1833 flies

UA 1833 flies BOS to EWR without a single fixed slot. Its most common scheduled departure was 06:00, used on 249 of 330 flights, with 06:05 (55 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 06:00249 flights75.5%
Departs 06:0555 flights16.7%

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 06:00 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and UA 1833 runs 5 points better at 94.4%. 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 1833 next to BOS to EWR

Every carrier on BOS to EWR combined arrived on time 74.9% of the time across 3,906 flights, so UA 1833 is 20 points ahead of it. United flew 2,719 flights on the same city pair under all its flight numbers, including this one, and those ran 75.5% on time. Across its whole network United Airlines managed 79.0%, which this flight beats by 15 points.

UA 1833 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
UA 1833thin sample	330	94.4%	66 min	3.03%	A−
All United Airlines on BOS–EWR	2,719	75.5%	84 min	3.46%	B−
All carriers on BOS–EWR	3,906	74.9%	79 min	4.33%	C−
United Airlines, whole network	821,041	79.0%	72 min	1.01%	B

Across the year

UA 1833 quarter by quarter

UA 1833 did not run the same all year. Its best quarter was Apr–Jun 2026 at 98.8% on time and its weakest Jan–Mar 2026 at 87.5%, a swing of 11 points on roughly 83 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 flights94.3%
Oct–Dec 202577 flights96.1%
Jan–Mar 202677 flights87.5%
Apr–Jun 202684 flights98.8%

Scale runs 80% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, UA 1833 did best on Thursday at 100.0% on time and worst on Saturday at 87.0%. Each day rests on about 47 flights, so a gap of 13 points is worth noticing but could still narrow in another year.

Delay causes

Why UA 1833 runs late

One category carries most of the weight here. Carrier accounts for 70% of the 1,192 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.

Carrier
70%
National Airspace System
29%
Extreme weather
2%

The largest share of delay minutes, 70%, 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 829 of the 1,192 delay minutes reported here. The split is drawn from 1,192 delay minutes reported on UA 1833.

Cancellations run at 3.03%, against 1.81% nationally. That is roughly one flight in 30 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 1.9% 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.

The same number turns up on eight other city pairs in the data, including EWR to CLE (40), EWR to EYW (37) and EWR to LAS (36), but none flew often enough under UA 1833 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to BOS to EWR only.

One caution: this is a thin sample. 330 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 1833

For a booking, the cancellation rate is the figure to plan around on UA 1833: 3.03% of its 330 scheduled flights did not operate. A late arrival costs about an hour, but a cancellation costs the day, so leave a later option open.

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