Carrier route record
UAEWR→SJU
United Airlines · Newark to San Juan
- Flights
- 1,113
- Period
- July 2025 to June 2026
- Share of route
- 53%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on EWR to SJU 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 1,113 flights, with a median arrival 4 minutes early.
The national on-time rate over the same period is 77.6%, so United on EWR to SJU runs 7 points behind the country as a whole. Across a thousand flights that is about 66 extra late arrivals.
Key figures
On time
71.0%
Arrivals under 15 minutes late, of 1,086 completed flights
Avg delay
75 min
Across delayed arrivals only, not all flights
Cancelled
2.34%
National rate is 1.81%
Whole route
70.7%
Every carrier on EWR to SJU, 2,101 flights
These figures cover 1,113 flights between July 2025 and June 2026. Beyond the headline rate, 9.7% 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.
Carrier by carrier
United against every carrier on EWR to SJU
United flew 1,113 of the 2,101 flights on EWR to SJU, most of the route. Its 71.0% on time is about level with the route as a whole at 70.7%. Ranked by on-time rate it is number two of four carriers on the route, where the range runs from JetBlue at 76.4% to Frontier at 54.4%. Two 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 |
|---|---|---|---|---|---|
| JetBlue Airways | 628 | 76.4% | 87 min | 3.34% | B− |
| United Airlines (this page) | 1,113 | 71.0% | 75 min | 2.34% | C |
| Spirit Airlinesthin sample | 146 | 67.9% | 72 min | 6.16% | C− |
| Frontier Airlinesthin sample | 214 | 54.4% | 102 min | 2.80% | F |
Flight by flight
United flight numbers on EWR to SJU
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 11 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–8am1 flights—
- 8am–11am729 flights74.0%
- 11am–2pm—
- 2pm–5pm19 flights—
- 5pm–8pm247 flights64.6%
- 8pm–5am117 flights63.5%
Scale runs 55% to 80%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 63.5% on time, against 74.0% for the 8am–11am 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 8am–11am window is the busiest, with 729 flights scheduled in it.
Across the year
United on EWR to SJU through the year
Delays peak in October, when the on-time rate falls to 51.6%. June is the strongest month at 85.6%. Moving a flexible trip across that boundary buys 34 points. December was the busiest month here, with 107 flights.
Across the week, Tuesday is the strongest day at 78.6% on time and Monday the weakest at 63.8%. 15 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. Carrier accounts for 46% of the 23,000 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.
- 46%Carrier
- 28%Late-arriving aircraft
- 23%National Airspace System
- 2%Extreme weather
The largest share of delay minutes, 46%, 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 11,000 of the 23,000 delay minutes reported here. The split is drawn from 23,483 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 74.0% on time here.
Cancellations sit at 2.34% against a national 1.81%, which is ordinary. Diversions add another 0.09%.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.7% 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 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.
The return leg is a different operation and performs like one: it runs 76.5% on time across 1,113 flights, 6 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 6 points of difference.
The sample behind these figures is 1,113 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 SJU
Put together: the calendar is the biggest lever here, not the carrier or the hour. June runs 85.6% on time and October 51.6%, a swing of 34 points. If the dates move at all, move them out of October before you think about anything else. 1,086 completed flights over 12 months sit behind that.
Related
Where to go next
- EWR to SJU, every carrier
- United on SJU to EWR, the return leg
- JetBlue Airways on EWR to SJU76.4%
- Spirit Airlines on EWR to SJU67.9%
- Frontier Airlines on EWR to SJU54.4%
- United Airlines network-wide record
- Newark Liberty International (EWR) delay statistics
- Luis Munoz Marin International (SJU) delay statistics
- How often a connection fails at the major US hubs
- 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.