Carrier route record

B6BOS→DTW

JetBlue Airways · Boston to Detroit

Flights: 723
Period: July 2025 to June 2026
Share of route: 28%
Carriers: 4

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

JetBlue on BOS to DTW sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 6 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 723 flights, with a median arrival 5 minutes early.

The national on-time rate over the same period is 77.6%, so JetBlue on BOS to DTW runs 6 points behind the country as a whole. Across a thousand flights that is about 59 extra late arrivals.

On time

71.7%

Arrivals under 15 minutes late, of 702 completed flights

Avg delay

72 min

Across delayed arrivals only, not all flights

Cancelled

2.77%

National rate is 1.81%

Whole route

77.6%

Every carrier on BOS to DTW, 2,591 flights

These figures cover 723 flights between July 2025 and June 2026. Beyond the headline rate, 11.7% 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.

Carrier by carrier

JetBlue against every carrier on BOS to DTW

JetBlue flew 723 of the 2,591 flights on BOS to DTW, about 28% of it. Its 71.7% on time is 6 points worse than the route as a whole, which runs 77.6%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from Republic at 100.0% to JetBlue at 71.7%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.

Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.

On-time performance by carrier on BOS to DTW
Airline	Flights	On time	Avg delay	Cancelled	Grade
Republic Airwaysthin sample	1	100.0%	—	0.00%	A+
Spirit Airlinesthin sample	155	82.6%	62 min	0.00%	B+
Delta Air Lines	1,712	79.6%	77 min	2.04%	B
JetBlue Airways (this page)	723	71.7%	72 min	2.77%	C

Departure window

When JetBlue runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 37 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am122 flights89.7%
8am–11am134 flights90.1%
11am–2pm44 flights72.1%
2pm–5pm176 flights61.2%
5pm–8pm123 flights68.1%
8pm–5am124 flights52.8%

Scale runs 45% to 95%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 52.8% on time, against 90.1% for the 8am–11am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 2pm–5pm window is the busiest, with 176 flights scheduled in it.

Across the year

JetBlue on BOS to DTW through the year

Darker means more delays. Figures are on-time percentages.September best, July worst

July is the worst month at 57.9% on time, 26 points below September, the best at 84.2%. 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. October was the busiest month here, with 100 flights.

Across the week, Wednesday is the strongest day at 82.0% on time and Sunday the weakest at 55.4%. 27 points is a smaller lever than departure hour, but it is free.

Delay causes

Why JetBlue runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 48% of the 14,000 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
48%
Carrier
31%
National Airspace System
17%
Extreme weather
3%
Security
0%

48% 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 14,000 reported delay minutes here, that single category outweighs weather by 15 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 14,387 reported delay minutes.

The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 90.1% on time here.

Cancellations run at 2.77%, against 1.81% nationally. That is roughly one flight in 40 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.

Connections and stage length

What a delay here costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 11.7% 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 632 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg runs 74.0% on time across 723 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 723 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 JetBlue on BOS to DTW

Put together: treat all of this as provisional. 723 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 71.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 702 completed flights over 12 months sit behind that.

Where to go next

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