Flight number record
B6 733
JetBlue Airways · Boston to San Francisco
- Route
- BOS → SFO
- Departs
- 17:20
- Flights
- 331
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s B6 733, check with JetBlue Airways.
B6 733 earns a D, which is as low as this site's scale goes for a reason. Only 55.9% of flights arrive inside the 15-minute window, 21 points worse than the national rate of 77.3%. Late arrivals average a little over an hour. Treat any tight connection here as a coin flip. That rests on 331 flights, with a median arrival 7 minutes late.
The national on-time rate over the same period is 77.3%, so B6 733 runs 21 points behind the country as a whole. Across a thousand flights that is about 214 extra late arrivals.
Key figures
On time
55.9%
Arrivals under 15 minutes late, of 324 completed flights
Avg delay
75 min
Across delayed arrivals only, not all flights
Cancelled
1.21%
National rate is 1.89%
1 hour+ late
19.8%
National rate is 8.3%
These figures cover 331 flights between September 2025 and August 2026. Beyond the headline rate, 19.8% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Schedule
When B6 733 flies
B6 733 flies BOS to SFO without a single fixed slot. Its most common scheduled departure was 17:20, used on 44 of 331 flights, with 17:59 (42 flights) next.
- Departs 17:2044 flights13.3%
- Departs 17:5942 flights12.7%
Scale runs 0% to 100%.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 17:20 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.0%, and B6 733 runs 12 points worse at 55.9%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
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Against the route
B6 733 next to BOS to SFO
Every carrier on BOS to SFO combined arrived on time 69.2% of the time across 4,817 flights, so B6 733 is 13 points behind it. JetBlue flew 1,808 flights on the same city pair under all its flight numbers, including this one, and those ran 66.5% on time. Across its whole network JetBlue Airways managed 71.3%, which this flight trails by 15 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| B6 733thin sample | 331 | 55.9% | 75 min | 1.21% | D |
| All JetBlue Airways on BOS–SFO | 1,808 | 66.5% | 67 min | 2.05% | C |
| All carriers on BOS–SFO | 4,817 | 69.2% | 66 min | 1.58% | C |
| JetBlue Airways, whole network | 240,615 | 71.3% | 77 min | 3.56% | C− |
Across the year
B6 733 quarter by quarter
B6 733 did not run the same all year. Its best quarter was Jan–Mar 2026 at 61.6% on time and its weakest Jul–Sep 2026 at 43.3%, a swing of 18 points on roughly 83 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
- Jul–Sep 202526 flights—
- Oct–Dec 202587 flights58.1%
- Jan–Mar 202690 flights61.6%
- Apr–Jun 202666 flights47.0%
- Jul–Sep 202662 flights43.3%
Scale runs 35% to 65%. Rows with fewer than 30 flights show a dash.
By weekday, B6 733 did best on Tuesday at 67.3% on time and worst on Thursday at 41.7%. Each day rests on about 47 flights, so a gap of 26 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late B6 733 runs when it is late
The 143 late arrivals split 37 under half an hour, 42 between 30 and 60 minutes, and 64 an hour or more.
- 15+ min early76 flights23.5%
- Within 15 min105 flights32.4%
- 15–29 min late37 flights11.4%
- 30–59 min late42 flights13.0%
- 1–2 hours late41 flights12.7%
- 2+ hours late23 flights7.1%
Scale runs 0% to 100%.
Share of 324 completed flights by arrival against schedule.
19 of 133 late departures made up the time and arrived on time, 14% of them. In the other direction, 29 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at SFO.
The worst days
Worst days for B6 733
The latest arrival of the period was on 20 February 2026, 7 hours 5 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The same cause led on four of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 20 February 2026 | 7 hours 5 minutes | Late-arriving aircraft |
| 8 November 2025 | 5 hours 58 minutes | Late-arriving aircraft |
| 17 April 2026 | 4 hours 9 minutes | Carrier |
| 25 February 2026 | 4 hours | Late-arriving aircraft |
| 5 November 2025 | 3 hours 47 minutes | Late-arriving aircraft |
Delay causes
Why B6 733 runs late
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 11,000 reported delay minutes.
- 38%Late-arriving aircraft
- 35%National Airspace System
- 26%Carrier
- 2%Extreme weather
38% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 11,000 reported delay minutes here, that single category outweighs weather by 20 to one. The split is drawn from 10,729 delay minutes reported on B6 733.
Cancellations sit at 1.21% against a national 1.89%, which is ordinary. Diversions add another 0.91%.
Connections and routes
What a delay on this flight costs
19.8% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
At 2,704 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.
Every one of the 331 flights under B6 733 in the data flew BOS to SFO. The number was not reused on any other city pair, which makes this a clean record of one route.
One caution: this is a thin sample. 331 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking B6 733
For a booking, B6 733 is a flight to put a long connection behind. 19.8% of its completed flights arrived an hour or more late, which a short layover will not absorb. If the onward flight is on a separate ticket, the risk sits with you.
Related
Where to go next
- BOS to SFO, every carrier and departure
- SFO to BOS, the return direction
- Delta Air Lines 1655 on the same route66.1%
- United Airlines 2400 on the same route51.1%
- United Airlines 2441 on the same route84.4%
- JetBlue Airways 333 on the same route54.3%
- United Airlines 1074 on the same route77.8%
- Boston Logan International (BOS) delay statistics
- San Francisco International (SFO) delay statistics
- JetBlue Airways on-time record
- Every JetBlue Airways flight number with a record
- The most and least reliable flight numbers in the US
- Why the first flight of the morning is statistically safest
A flight number here means JetBlue Airways’s own number as it reports to the DOT. How the figures are computed is on the methodology page.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.