Route profile
EWR→SJU
Flight reliability, delays and best times to fly from Newark to San Juan, 1,608 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 6% of comparable major US routes (4,598 compared)
Calculated from 6,837 flights. How this is calculated · What counts as on time
EWR → SJU arrives on time 70.0% of the time; the return trip, SJU → EWR, arrives on time 73.2% of the time, a 3.2-point gap between the two directions of the same city pair.
EWR → SJU spends 31.7 minutes on the ground on a 1,608-mile trip: 25.7 minutes from pushback to wheels-up at EWR and 6.1 minutes from touchdown to gate at SJU.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
This route's worst arrivals run unusually far past its typical one, a bigger gap than 93% of 4,598 comparable routes.
A typical arrival is 3 min early, but the worst tenth run 74 minutes worse than that.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,598 in the comparison.
What sets this route apart
Where EWR to SJU differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
EWR to SJU struggles most at 5 PM: 45.7% of its flights scheduled then arrive on time, 24.6 points behind the 70.3% on routes of similar length at the same hour. Against all other routes the gap is 24.1 points.
Saturday is the day EWR to SJU slips furthest against routes of similar length, 68.7% on time where they average 78.8%, 10.1 points lower. Against all other routes the gap is 10.4 points.
In August, EWR to SJU runs 14.6 points below routes of similar length, 61.6% on time to 76.2%. Against all other routes the gap is 14.9 points.
Spirit Airlines’ flights on EWR to SJU arrive on time 65.2% of the time, 11.1 points below the 76.3% it manages on its routes of similar length. Against all other routes the gap is 10.1 points.
JetBlue does better on EWR to SJU than on its routes of similar length: 73.2% on time here, 69.0% there, 4.2 points apart.
EWR to SJU against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 5 PM departures | 45.7% | routes of similar length | 70.3% | −24.6 pts | 138 here, 108,802 there |
| Weekday: Saturday | 68.7% | routes of similar length | 78.8% | −10.1 pts | 934 here, 214,323 there |
| Month: August | 61.6% | routes of similar length | 76.2% | −14.6 pts | 599 here, 139,548 there |
| Airline: Spirit Airlines | 65.2% | routes of similar length | 76.3% | −11.1 pts | 644 here, 54,658 there |
| Airline: JetBlue | 73.2% | routes of similar length | 69.0% | +4.2 pts | 1,876 here, 51,515 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 1,608 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
Why EWR → SJU flights are cancelled
July 2023 – July 2026
EWR → SJU cancelled 134 of 6,837 scheduled flights — about 1 in every 51. The reason filed most often was extreme weather, 50.7% of the cancellations coded on this route — about 1 in every 101 scheduled flights.
Share of cancellations
Of 134 cancelled departures carrying a reason code.
What each reason means
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
68 cancellations, 50.7% of the total.
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
39 cancellations, 29.1% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
27 cancellations, 20.1% of the total.
A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.
0 cancellations, 0.0% of the total.
Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
134 coded cancellations were recorded on EWR → SJU; the section appears from 50.
When it goes wrong
July 2023 – July 2026
71 min late
against a median of 3 min early
EWR → SJU has an average that understates its risk: a typical arrival is 3 min early, but the worst tenth are 74 minutes worse than that. If the trip has something unmissable at the end of it, the median is the wrong number to plan against.
Percentiles over 6,837 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at SJU after arriving from EWR.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 45% | Likely to miss |
| 45 min | 29% | High risk |
| 60 min | 20% | High risk |
| 90 min | 12% | Some risk |
| 120 min | 7.8% | Some risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 1.96% of the time and diverts 0.23% of the time, which a late arrival never shows up in.
Chance of missing is the share of 6,687 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 71 minutes late (90th-percentile gate arrival delay), over 6,837 operations.
Any other layover length: connection checker.
Best time to fly
EWR → SJU flights departing 5–9 AM arrived on time 76.3% of the time, against 62.0% for 9 PM–5 AM departures, a gap of 14.3 percentage points.
By departure window
By departure hour
- 12 AM to 4 AM: too few flights to score
- 5 AM: 77.3% on time from 301 flights
- 6 AM: 75.0% on time from 422 flights
- 7 AM: 74.4% on time from 829 flights
- 8 AM: 78.7% on time from 701 flights
- 9 AM: 77.3% on time from 1,142 flights
- 10 AM: 77.1% on time from 190 flights
- 11 AM: 60.9% on time from 380 flights
- 12 PM: too few flights to score
- 1 PM: 58.7% on time from 201 flights
- 2 PM to 3 PM: too few flights to score
- 4 PM: 76.1% on time from 201 flights
- 5 PM: 45.7% on time from 143 flights
- 6 PM: too few flights to score
- 7 PM: 60.6% on time from 1,218 flights
- 8 PM: 65.3% on time from 273 flights
- 9 PM: 70.3% on time from 204 flights
- 10 PM: 56.5% on time from 397 flights
- 11 PM: too few flights to score
Why EWR → SJU runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for EWR → SJU. Only delays of 15 minutes or more are attributed. What the five causes mean
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 3,397 | 71.6% | 1.41% | -3 min | 10.5% |
| JetBlue | 1,920 | 73.2% | 2.24% | -5 min | 11.4% |
| Frontier Airlines | 851 | 59.8% | 2.12% | 7 min | 15.9% |
| Spirit Airlines | 669 | 65.2% | 3.74% | -2 min | 17.1% |
United Airlines flew 49.7% of the 6,837 flights listed. Spirit Airlines cancelled 3.74% of its flights here against 1.41% for United Airlines.
JetBlue arrived on time 13.4 percentage points more often than Frontier Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
UA1556 (9:46 AM) arrived on time 77.2% of the time, 14.7 points more often than UA1543 (7:58 PM) at 62.5%.
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Thursday the least, a gap of 7.2 percentage points.
By month
- Jan: 67.0%
- Feb: 71.6%
- Mar: 70.1%
- Apr: 74.2%
- May: 75.8%
- Jun: 74.5%
- Jul: 57.2%
- Aug: 61.6%
- Sep: 80.2%
- Oct: 75.6%
- Nov: 72.5%
- Dec: 68.9%
July is historically the weakest month and September the strongest, a spread of 23.0 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 42.4% from 217 flights
- August 2023: 56.8% from 216 flights
- September 2023: 77.9% from 160 flights
- October 2023: 87.0% from 154 flights
- November 2023: 80.5% from 149 flights
- December 2023: 76.7% from 189 flights
- January 2024: 69.3% from 201 flights
- February 2024: 78.5% from 175 flights
- March 2024: 71.3% from 161 flights
- April 2024: 74.4% from 158 flights
- May 2024: 76.9% from 186 flights
- June 2024: 65.5% from 184 flights
- July 2024: 60.1% from 213 flights
- August 2024: 59.4% from 204 flights
- September 2024: 87.6% from 170 flights
- October 2024: 76.7% from 177 flights
- November 2024: 75.9% from 197 flights
- December 2024: 66.5% from 226 flights
- January 2025: 66.2% from 218 flights
- February 2025: 68.9% from 192 flights
- March 2025: 66.4% from 213 flights
- April 2025: 69.0% from 206 flights
- May 2025: 67.6% from 207 flights
- June 2025: 74.4% from 180 flights
- July 2025: 65.2% from 199 flights
- August 2025: 69.3% from 193 flights
- September 2025: 74.3% from 152 flights
- October 2025: 62.0% from 144 flights
- November 2025: 59.3% from 145 flights
- December 2025: 63.9% from 199 flights
- January 2026: 65.5% from 214 flights
- February 2026: 67.5% from 180 flights
- March 2026: 73.3% from 188 flights
- April 2026: 79.6% from 191 flights
- May 2026: 86.6% from 135 flights
- June 2026: 84.4% from 161 flights
- July 2026: 62.6% from 183 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 70.4% against 69.9% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 6,837 EWR → SJU flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed