Carrier performance at one airport
B6→SJU
JetBlue Airways at Luis Munoz Marin International
- Departures
- 11,772
- Period
- July 2025 to June 2026
- Routes
- 18
- Rank here
- #5 of 7
JetBlue Airways at San Juan sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 11,772 flights, of which Delta Air Lines flew 3,636 at 87.9% on time.
Measured against the airport rather than the country, JetBlue Airways runs 3 points behind the 77.8% weighted average across all carriers at SJU. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
74.9%
11,505 completed departures
Avg delay
75 min
Across delayed flights only
Cancelled
1.90%
At SJU, this carrier only
Rank here
#5
Of 7 carriers clearing the floor at SJU
These figures cover 12,000 flights between July 2025 and June 2026. Beyond the headline rate, 9.8% 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.
Against the competition
Every carrier at SJU, ranked
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 87.9% of the time; Frontier Airlines manages 71.6%. Sample sizes sit next to every figure, because a two-point gap across 4,867 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 3,636 | 87.9% | 73 min | 1.51% | A |
| United Airlines | 3,591 | 83.7% | 67 min | 1.23% | B |
| Southwest Airlines | 3,905 | 80.3% | 48 min | 0.79% | B+ |
| American Airlines | 4,897 | 80.2% | 96 min | 1.39% | B |
| JetBlue Airways (this page) | 11,772 | 74.9% | 75 min | 1.90% | C |
| Spirit Airlines | 2,723 | 71.7% | 76 min | 4.19% | C− |
| Frontier Airlines | 4,867 | 71.6% | 93 min | 2.30% | C |
Spirit Airlines cancels 4.2% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Route by route
Where JetBlue Airways flies from SJU
JetBlue Airways operates 18 routes out of SJU with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SJU to JFK · New York | 2,237 | 75.0% | 78 min | 3.22% | B− |
| SJU to MCO · Orlando | 2,130 | 76.9% | 72 min | 1.03% | B |
| SJU to FLL · Fort Lauderdale | 1,645 | 76.6% | 71 min | 1.28% | B |
| SJU to BOS · Boston | 1,415 | 69.9% | 75 min | 2.97% | C |
| SJU to BDL · Hartford | 726 | 69.3% | 78 min | 1.93% | C |
| SJU to EWR · Newark | 626 | 75.4% | 80 min | 2.88% | B |
| SJU to TPA · Tampa | 614 | 75.9% | 66 min | 0.49% | B+ |
| SJU to DCA · Washington | 365 | 69.9% | 87 min | 1.37% | C |
| SJU to HPN · White Plainsthin sample | 359 | 72.3% | 105 min | 2.51% | C |
| SJU to STT · Charlotte Amaliethin sample | 351 | 71.6% | 63 min | 0.57% | C+ |
| SJU to RDU · Raleighthin sample | 333 | 85.7% | 74 min | 1.50% | A |
| SJU to PVD · Providencethin sample | 324 | 68.1% | 66 min | 1.85% | C |
| SJU to STX · Christianstedthin sample | 312 | 76.7% | 50 min | 0.96% | B+ |
| SJU to PHL · Philadelphiathin sample | 97 | 95.8% | 25 min | 0.00% | A+ |
| SJU to JAX · Jacksonvillethin sample | 86 | 81.2% | 81 min | 1.16% | B |
| SJU to ORF · Norfolkthin sample | 55 | 92.7% | 51 min | 0.00% | A+ |
| SJU to BUF · Buffalothin sample | 55 | 87.3% | 85 min | 0.00% | A+ |
| SJU to RIC · Richmondthin sample | 42 | 82.9% | 90 min | 2.38% | B |
Departure window
Best time of day for this operation
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 20 points, against 16 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am2,354 flights87.3%
- 8am–11am1,216 flights83.4%
- 11am–2pm1,883 flights76.0%
- 2pm–5pm2,297 flights67.5%
- 5pm–8pm2,446 flights69.0%
- 8pm–5am1,576 flights68.2%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 87.3% of the time, against 67.5% for the afternoon window. That is 20 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5pm–8pm window is the busiest, with 2,446 flights scheduled in it.
Across the year
Seasonal pattern
August is the worst month at 66.9% on time, 19 points below May, the best at 85.5%. 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. June was the busiest month here, with 1,180 flights.
Delay causes
What holds this operation up
- 51%Late-arriving aircraft
- 36%Carrier
- 12%National Airspace System
- 1%Extreme weather
- 0%Security
51% 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 216,000 reported delay minutes here, that single category outweighs weather by 51 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 215,769 reported delay minutes.
Cancellations sit at 1.90% against a national 1.81%, which is ordinary. Diversions add another 0.37%.
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 9.8% 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.
The sample behind these figures is 11,772 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.
Put together: the calendar is the biggest lever here, not the carrier or the hour. May runs 85.5% on time and August 66.9%, a swing of 19 points. If the dates move at all, move them out of August before you think about anything else. 11,505 completed flights over 12 months sit behind that.
Common questions
JetBlue Airways at SJU
How often is JetBlue Airways at SJU delayed?
About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 25.1% of the 11,772 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on JetBlue Airways at SJU?
Delta Air Lines leads at 87.9% on time across 3,636 flights. Frontier Airlines is at the other end on 71.6%, a gap of 16 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on JetBlue Airways at SJU?
The 5am–8am departure window is the strongest at 87.3% on time. The 2pm–5pm window is the weakest at 67.5%, 20 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are August delays on JetBlue Airways at SJU?
August is the weakest month at 66.9% on time, compared with 85.5% in May. Across the year that is 19 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.