Carrier route record

DLBOS→DFW

Delta Air Lines · Boston to Dallas-Fort Worth

Flights: 861
Period: July 2025 to June 2026
Share of route: 23%
Carriers: 4

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

Delta on BOS to DFW sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 8 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 861 flights, with a median arrival 6 minutes early.

The national on-time rate over the same period is 77.6%, so Delta on BOS to DFW runs 8 points behind the country as a whole. Across a thousand flights that is about 76 extra late arrivals.

On time

70.0%

Arrivals under 15 minutes late, of 832 completed flights

Avg delay

79 min

Across delayed arrivals only, not all flights

Cancelled

2.21%

National rate is 1.81%

Whole route

76.1%

Every carrier on BOS to DFW, 3,740 flights

These figures cover 861 flights between July 2025 and June 2026. Beyond the headline rate, 13.9% 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.

Carrier by carrier

Delta against every carrier on BOS to DFW

Delta flew 861 of the 3,740 flights on BOS to DFW, about 23% of it. Its 70.0% on time is 6 points worse than the route as a whole, which runs 76.1%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from JetBlue at 78.4% to Delta at 70.0%. 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 DFW
Airline	Flights	On time	Avg delay	Cancelled	Grade
JetBlue Airwaysthin sample	231	78.4%	77 min	3.46%	B−
American Airlines	2,633	78.0%	87 min	3.46%	B−
Spirit Airlinesthin sample	15	73.3%	88 min	0.00%	C+
Delta Air Lines (this page)	861	70.0%	79 min	2.21%	C

Flight by flight

Delta flight numbers on BOS to DFW

Departure window

When Delta runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 29 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–8am276 flights79.3%
8am–11am68 flights76.2%
11am–2pm48 flights76.6%
2pm–5pm160 flights59.9%
5pm–8pm234 flights68.8%
8pm–5am75 flights50.7%

Scale runs 40% to 85%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 50.7% on time, against 79.3% for the 5am–8am 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 5am–8am window is the busiest, with 276 flights scheduled in it.

Across the year

Delta on BOS to DFW through the year

Darker means more delays. Figures are on-time percentages.March best, December worst

December is the weak month at 57.4% on time, against 82.1% in March. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. July was the busiest month here, with 88 flights.

Across the week, Friday is the strongest day at 72.6% on time and Sunday the weakest at 62.9%. 10 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Delta runs late on this route

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 20,000 reported delay minutes.

Late-arriving aircraft
39%
Carrier
33%
National Airspace System
27%
Extreme weather
1%

39% 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 20,000 reported delay minutes here, that single category outweighs weather by 39 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 19,616 reported delay minutes.

The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 79.3% on time here.

Cancellations sit at 2.21% against a national 1.81%, which is ordinary. Diversions add another 1.16%.

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. 13.9% 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 1,562 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.

The return leg is a different operation and performs like one: it runs 77.4% on time across 861 flights, 7 points above this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 7 points of difference.

One caution: this is a thin sample. 861 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 Delta on BOS to DFW

Put together: treat all of this as provisional. 861 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 70.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 832 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