Carrier route record
UAEWR→SAN
United Airlines · Newark to San Diego
- Flights
- 1,233
- Period
- July 2025 to June 2026
- Share of route
- 79%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on EWR to SAN lands a B, 3 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 1,233 flights, with a median arrival 9 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate United on EWR to SAN from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
80.5%
Arrivals under 15 minutes late, of 1,203 completed flights
Avg delay
64 min
Across delayed arrivals only, not all flights
Cancelled
1.38%
National rate is 1.81%
Whole route
79.9%
Every carrier on EWR to SAN, 1,561 flights
These figures cover 1,233 flights between July 2025 and June 2026. The median arrival is 9 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.
Carrier by carrier
United against every carrier on EWR to SAN
United flew 1,233 of the 1,561 flights on EWR to SAN, most of the route. Its 80.5% on time is about level with the route as a whole at 79.9%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from United at 80.5% to Alaska at 77.6%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines (this page) | 1,233 | 80.5% | 64 min | 1.38% | B |
| Alaska Airlinesthin sample | 328 | 77.6% | 73 min | 3.96% | B− |
Flight by flight
United flight numbers on EWR to SAN
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 38 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am358 flights92.9%
- 8am–11am355 flights80.6%
- 11am–2pm7 flights—
- 2pm–5pm138 flights66.7%
- 5pm–8pm334 flights76.4%
- 8pm–5am41 flights55.0%
Scale runs 45% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 55.0% on time, against 92.9% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 5am–8am window is the busiest, with 358 flights scheduled in it.
Across the year
United on EWR to SAN through the year
June is the worst month at 71.4% on time, 20 points below March, the best at 91.3%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. August was the busiest month here, with 124 flights.
Across the week, Monday is the strongest day at 86.0% on time and Sunday the weakest at 74.4%. 12 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
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 15,000 reported delay minutes.
- 37%Late-arriving aircraft
- 32%National Airspace System
- 27%Carrier
- 4%Extreme weather
37% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 15,000 reported delay minutes here, that single category outweighs weather by 10 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 15,003 reported delay minutes.
32% 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 4,826 minutes out of 15,000, against a national NAS share of 21%.
Cancellations sit at 1.38% against a national 1.81%, which is ordinary. Diversions add another 1.05%.
Connections and stage length
What a delay here costs
6.5% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.
At 2,425 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 return leg runs 82.9% on time across 1,233 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 1,233 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking United on EWR to SAN
Put together: the calendar is the biggest lever here, not the carrier or the hour. March runs 91.3% on time and June 71.4%, a swing of 20 points. If the dates move at all, move them out of June before you think about anything else. 1,203 completed flights over 12 months sit behind that.
Related
Where to go next
- EWR to SAN, every carrier
- United on SAN to EWR, the return leg
- Alaska Airlines on EWR to SAN77.6%
- United Airlines network-wide record
- Newark Liberty International (EWR) delay statistics
- San Diego International (SAN) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.