Flight number record

UA 648

United Airlines · Newark to San Francisco

Route: EWR → SFO
Departs: 10:00
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s UA 648, check with United Airlines.

UA 648 sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 7 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 365 flights, with a median arrival 3 minutes early.

The national on-time rate over the same period is 77.6%, so UA 648 runs 7 points behind the country as a whole. Across a thousand flights that is about 73 extra late arrivals.

On time

70.3%

Arrivals under 15 minutes late, of 357 completed flights

Avg delay

79 min

Across delayed arrivals only, not all flights

Cancelled

1.37%

National rate is 1.81%

1 hour+ late

11.5%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. Beyond the headline rate, 11.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Schedule

When UA 648 flies

UA 648 flies EWR to SFO without a single fixed slot. Its most common scheduled departure was 10:00, used on 152 of 365 flights, with 10:35 (79 flights) and 10:40 (41 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 10:00152 flights41.6%
Departs 10:3579 flights21.6%
Departs 10:4041 flights11.2%

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 10:00 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and UA 648 runs 14 points worse at 70.3%. 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 648 next to EWR to SFO

Every carrier on EWR to SFO combined arrived on time 69.8% of the time across 4,403 flights, so UA 648 is about level with it. United flew 3,793 flights on the same city pair under all its flight numbers, including this one, and those ran 68.9% on time. Across its whole network United Airlines managed 79.0%, which this flight trails by 9 points.

UA 648 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
UA 648	365	70.3%	79 min	1.37%	C
All United Airlines on EWR–SFO	3,793	68.9%	92 min	2.53%	C
All carriers on EWR–SFO	4,403	69.8%	89 min	2.32%	C
United Airlines, whole network	821,041	79.0%	72 min	1.01%	B

Across the year

UA 648 quarter by quarter

UA 648 did not run the same all year. Its best quarter was Jan–Mar 2026 at 82.6% on time and its weakest Oct–Dec 2025 at 58.2%, a swing of 24 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 flights73.3%
Oct–Dec 202592 flights58.2%
Jan–Mar 202690 flights82.6%
Apr–Jun 202691 flights67.8%

Scale runs 50% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, UA 648 did best on Tuesday at 78.8% on time and worst on Friday at 63.5%. Each day rests on about 52 flights, so a gap of 15 points is worth noticing but could still narrow in another year.

Delay causes

Why UA 648 runs late

Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 8,363 reported delay minutes.

Carrier
39%
Late-arriving aircraft
30%
National Airspace System
30%
Extreme weather
1%

The largest share of delay minutes, 39%, 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 3,241 of the 8,363 delay minutes reported here. The split is drawn from 8,363 delay minutes reported on UA 648.

Cancellations sit at 1.37% against a national 1.81%, which is ordinary. Diversions add another 0.82%.

Connections and routes

What a delay on this flight costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 11.5% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.

At 2,565 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 four other city pairs in the data, including SFO to ORD (14), PBI to EWR (9) and STL to EWR (6), but none flew often enough under UA 648 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to EWR to SFO only.

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 648

For a booking, read UA 648 as 70.3% 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