Flight number record

B6 333

JetBlue Airways · Boston to San Francisco

Route: BOS → SFO
Departs: 16:40
Flights: 332
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s B6 333, check with JetBlue Airways.

B6 333 earns a D, which is as low as this site's scale goes for a reason. Only 56.9% of flights arrive inside the 15-minute window, 21 points worse than the national rate of 77.6%. Late arrivals average a little over an hour. Treat any tight connection here as a coin flip. That rests on 332 flights, with a median arrival 8 minutes late.

The national on-time rate over the same period is 77.6%, so B6 333 runs 21 points behind the country as a whole. Across a thousand flights that is about 207 extra late arrivals.

On time

56.9%

Arrivals under 15 minutes late, of 325 completed flights

Avg delay

69 min

Across delayed arrivals only, not all flights

Cancelled

1.51%

National rate is 1.81%

1 hour+ late

16.9%

National rate is 8.1%

These figures cover 332 flights between July 2025 and June 2026. Beyond the headline rate, 16.9% 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.

Schedule

When B6 333 flies

B6 333 flies BOS to SFO without a single fixed slot. Its most common scheduled departure was 16:40, used on 38 of 332 flights. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 16:4038 flights11.4%

Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.

Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.

A 16:40 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and B6 333 runs 16 points worse at 56.9%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

B6 333 next to BOS to SFO

Every carrier on BOS to SFO combined arrived on time 72.6% of the time across 4,676 flights, so B6 333 is 16 points behind it. JetBlue flew 1,676 flights on the same city pair under all its flight numbers, including this one, and those ran 70.5% on time. Across its whole network JetBlue Airways managed 72.7%, which this flight trails by 16 points.

B6 333 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
B6 333thin sample	332	56.9%	69 min	1.51%	D
All JetBlue Airways on BOS–SFO	1,676	70.5%	65 min	1.31%	C
All carriers on BOS–SFO	4,676	72.6%	65 min	1.22%	C
JetBlue Airways, whole network	234,468	72.7%	76 min	2.56%	C

Across the year

B6 333 quarter by quarter

B6 333 did not run the same all year. Its best quarter was Jul–Sep 2025 at 70.7% on time and its weakest Oct–Dec 2025 at 50.0%, a swing of 21 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 202584 flights70.7%
Oct–Dec 202582 flights50.0%
Jan–Mar 202677 flights56.8%
Apr–Jun 202689 flights50.6%

Scale runs 40% to 75%. Rows with fewer than 30 flights show a dash.

By weekday, B6 333 did best on Wednesday at 66.7% on time and worst on Friday at 44.2%. Each day rests on about 47 flights, so a gap of 23 points is worth noticing but could still narrow in another year.

Delay causes

Why B6 333 runs late

One category carries most of the weight here. Late-arriving aircraft accounts for 55% of the 9,596 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.

Late-arriving aircraft
55%
National Airspace System
27%
Carrier
16%
Extreme weather
2%
Security
0%

55% 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 9,596 reported delay minutes here, that single category outweighs weather by 33 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 9,596 delay minutes reported on B6 333.

Cancellations sit at 1.51% against a national 1.81%, which is ordinary. Diversions add another 0.60%.

Connections and routes

What a delay on this flight costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 16.9% 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 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 332 flights under B6 333 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. 332 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 333

For a booking, B6 333 is a flight to put a long connection behind. 16.9% 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.

Where to go next

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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures