Flight profile · JetBlue
B6561
Boston (BOS) to San Juan (SJU) · scheduled 8:45 PM – 12:49 AM
How B6561 performs
959 operations, July 2023 – July 2026.
B6561 arrived on time 63.3% of the time, against 67.7% for all BOS → SJU flights, so this departure is 4.4 percentage points worse than the route as a whole. Against JetBlue’s own flights on this route it is 4.3 points worse.
Source: US DOT Bureau of Transportation Statistics · 959 operations, July 2023 – July 2026 · If B6561 is cancelled or significantly changed, DOT’s automatic refund rule may entitle you to your money back. The refund checker walks through eligibility.
Where B6561 is right now
A live reading, only if you ask for it. It is not part of the reliability record above.
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Against the rest of the route
| Flight or route | On time | Cancelled | Median delay | Severe | Flights |
|---|---|---|---|---|---|
| B6561 | 63.3% | 1.98% | 3 min | 14.8% | 959 |
| JetBlue on BOS → SJU | 67.6% | 1.50% | 0 min | 12.7% | 3,865 |
| All BOS → SJU flights | 67.7% | 1.70% | 0 min | 12.3% | 5,995 |
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026
Why B6561 runs late
Where US DOT attributed the delay minutes on this flight.
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 B6561 on BOS → SJU. Only delays of 15 minutes or more are attributed.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
Does a late aircraft delay this flight?
How often the plane that flies B6561 comes in late, and what that does to the departure.
When the aircraft came in 15 or more minutes late, B6561 pushed back an average of 57 minutes late; when it came in on time or early, an average of 9 minutes late.
Each departure is matched to the flight the same aircraft flew into BOS just before it, using the tail number in the DOT file, 485 of 940 departures in all. A departure is left out when that flight is unknown, was cancelled or diverted, or the aircraft had sat for more than 12 hours. A flight the airline cancelled never left and is not in the count, and one flown by a substitute aircraft is matched to the aircraft that flew it, not to the one first planned.
Against the network at the same turn length
| Share of departures | Inbound landed 15+ late | Left 15+ late after a late inbound | Left 15+ late after an on-time inbound |
|---|---|---|---|
| B6561 | 30% | 70% | 21% |
| Network, same turn | 17% | 68% | 9% |
The schedule leaves a normal turn: enough time to clean and board if the aircraft is on time, little to spare if it is not.
The network row is every flight with a scheduled turn of 60 to 89 minutes. How often B6561’s aircraft landed 15 or more minutes late is higher than the network’s and, once the aircraft was late, how often B6561 left 15 or more minutes late is about the same as the network’s.
More: Which Flight Numbers Pay for a Late Aircraft lists the flight numbers that pass a late aircraft on.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
From pushback to gate
When it leaves BOS late, does that still matter by the time it reaches SJU?
B6561 pushes back an average of 25.7 minutes late and reaches the gate at SJU an average of 21.7 minutes late. The 4.1 minutes between those two figures are slack the published schedule already carries, which is why a late pushback on this flight does not reliably become a late arrival. It spends 18.4 minutes on the taxiways at BOS, 1.9 minutes shorter than a typical BOS departure in the same hour.
On arrival at SJU, B6561 spends 6.1 min taxiing from touchdown to the gate — ground time a connecting passenger sits through before they can even leave the aircraft, on top of however late the flight itself ran. That is about what any arrival at SJU spends on the ground before reaching the gate.
Departure delay is averaged over every pushback and arrival delay over every completed arrival, so the two counts differ by the flights that never reached SJU. Taxi-out is gate to wheels up and sits inside the scheduled block rather than on top of it; the comparison is 22,665 departures from BOS scheduled in the clock hour B6561 most often leaves in. Taxi-in is landing to gate, compared against every arrival FlyerIntel has on file at SJU (109,607 flights), not just B6561’s own. More on taxi time.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026
The hour it leaves BOS
Part of any flight’s record belongs to the clock rather than to the flight. B6561 has one departure time, so this is what that time is worth.
On-time arrival rate. 22,665 departures from BOS are scheduled in the 8 PM–9 PM hour over the period, against 440,893 across the whole day.
B6561 is scheduled out of BOS at 8:45 PM, in the 8 PM–9 PM bank. Departures from BOS in that hour arrive on time 63.2% of the time against 77.2% across the airport’s whole day — the slot alone is worth 14.0 points worse before anything about this particular flight is considered.
The two airport figures cover every departure from BOS to every destination, so they describe the slot rather than this journey — the like-for-like comparison against the route is above. Hours are scheduled local, and a number whose schedule moved between banks inside the period has no single hour and is not described here at all. Why the hour matters.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Hours below 120 departures are not scored.
By day of week
Does B6561 run worse on particular days?
Wednesday is historically the most reliable day and Sunday the least, a gap of 12.8 percentage points.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Days with fewer than 120 operations are not scored.
Other routes B6561 has flown
A flight number is a slot in a schedule, and carriers reassign it. These are the other city pairs this number served in the analysis period.
| Route | Operated | Flights | On time |
|---|---|---|---|
| LGA→PBI New York to West Palm Beach | September 4, 2024 – October 26, 2024 | 53 | — |
Because the same number has served different journeys, the statistics above describe only the route B6561 currently operates. Blending them would produce an average of two different flights.
When it goes wrong
The average describes a usual day. This is the day that ruins a connection.
86 min late
against a median of 3 min late
B6561 has an average that understates its risk: a typical arrival is 3 min late, but the worst tenth are 83 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 959 operations; cancelled and diverted flights are counted separately.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
Other flights on this route
Same airports, same journey, different odds of arriving on time.
| Flight | Airline | On time | Median arrival | Operations |
|---|---|---|---|---|
| DL1780 | Delta Air Lines | 80.2% | 7 min early | 1,127 |
| B6861 | JetBlue | 72.7% | 3 min early | 1,033 |
| B6561 this flight | JetBlue | 63.3% | 3 min late | 959 |
Every departure listed carries at least 600 operations, so the comparison is between figures that mean something. B6561 is placed in the same ordering rather than left out of it; the rows around it are the most punctual departures on the route, not all of them, so this is a comparison and not a rank. Schedules change; confirm the departure still operates before booking around this.
Data and methodology
Calculated by FlyerIntel from 959 records of B6561 operating BOS → SJU, published by the US DOT Bureau of Transportation Statistics. A flight counts as delayed when it arrives 15 or more minutes after schedule. Cancelled and diverted flights are excluded from the on-time rate and reported separately. Flight numbers are resolved as carrier plus number plus route, because the same number serves different routes over time.
Full methodology · Data sources · Report a problem
Related research: Most and Least Reliable Flight Numbers · The Delay You Inherit · Making Up Time in the Air
Analysis last recomputed