Flight number record

DL 2351

Delta Air Lines · Dallas-Fort Worth to Boston

Route: DFW → BOS
Departs: 07:05
Flights: 348
Period: September 2025 to August 2026

Historical statistics for September 2025 to August 2026, not live status. For today’s DL 2351, check with Delta Air Lines.

DL 2351 earns an A. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 11 points better than the national rate of 77.3%. When something does go wrong the average delay runs an hour and a half. That rests on 348 flights, with a median arrival 11 minutes early.

Set against the rest of the country, DL 2351's record is 11 points better than the US average of 77.3%. That gap is worth roughly 109 fewer late arrivals for every thousand flights.

On time

88.2%

Arrivals under 15 minutes late, of 338 completed flights

Avg delay

89 min

Across delayed arrivals only, not all flights

Cancelled

2.59%

National rate is 1.89%

1 hour+ late

4.4%

National rate is 8.3%

These figures cover 348 flights between September 2025 and August 2026. The median arrival is 11 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.

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Schedule

When DL 2351 flies

DL 2351 flies DFW to BOS without a single fixed slot. Its most common scheduled departure was 07:05, used on 97 of 348 flights, with 07:00 (78 flights) and 07:20 (59 flights) next.

Departs 07:0597 flights27.9%
Departs 07:0078 flights22.4%
Departs 07:2059 flights17.0%

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 07:05 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and DL 2351 runs level with that at 88.2%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

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Against the route

DL 2351 next to DFW to BOS

Every carrier on DFW to BOS combined arrived on time 67.2% of the time across 3,695 flights, so DL 2351 is 21 points ahead of it. Delta flew 868 flights on the same city pair under all its flight numbers, including this one, and those ran 76.2% on time. Across its whole network Delta Air Lines managed 81.1%, which this flight beats by 7 points.

DL 2351 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 2351thin sample	348	88.2%	89 min	2.59%	A
All Delta Air Lines on DFW–BOS	868	76.2%	86 min	2.42%	B
All carriers on DFW–BOS	3,695	67.2%	73 min	3.11%	C−
Delta Air Lines, whole network	1,039,517	81.1%	71 min	1.74%	B

Across the year

DL 2351 quarter by quarter

Quarter by quarter DL 2351 held fairly steady: 90.0% in Oct–Dec 2025, 87.3% in Jan–Mar 2026, 87.8% in Apr–Jun 2026 and 86.7% in Jul–Sep 2026. A spread of 3 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202530 flights—
Oct–Dec 202580 flights90.0%
Jan–Mar 202685 flights87.3%
Apr–Jun 202691 flights87.8%
Jul–Sep 202662 flights86.7%

Scale runs 80% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, DL 2351 did best on Thursday at 93.9% on time and worst on Saturday at 81.2%. Each day rests on about 50 flights, so a gap of 13 points is worth noticing but could still narrow in another year.

Arrival by arrival

How late DL 2351 runs when it is late

DL 2351 often beats the schedule: 139 of 338 completed flights, 41%, arrived 15 minutes or more early. The 40 late arrivals split 15 under half an hour, 10 between 30 and 60 minutes, and 15 an hour or more.

15+ min early139 flights41.1%
Within 15 min159 flights47.0%
15–29 min late15 flights4.4%
30–59 min late10 flights3.0%
1–2 hours late5 flights1.5%
2+ hours late10 flights3.0%

Scale runs 0% to 100%.

Share of 338 completed flights by arrival against schedule.

10 of 34 late departures made up the time and arrived on time, 29% of them. 16 flights left on time and still arrived late.

The worst days

Worst days for DL 2351

The latest arrival of the period was on 7 June 2026, 9 hours 31 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The five worst days are spread across June, May, March and July, with no single month standing out.

The latest arrivals of DL 2351 in the period
Date	Arrived late by	Largest filed cause
7 June 2026	9 hours 31 minutes	Carrier
27 May 2026	7 hours 37 minutes	Late-arriving aircraft
6 March 2026	5 hours 13 minutes	Carrier
19 June 2026	3 hours 42 minutes	Extreme weather
13 July 2026	2 hours 37 minutes	Extreme weather

Delay causes

Why DL 2351 runs late

Carrier accounts for 49% of the 3,570 delay minutes carriers reported here, and the remaining four split what is left.

Carrier
49%
National Airspace System
20%
Extreme weather
18%
Late-arriving aircraft
12%

Extreme weather accounts for 18% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the quarterly figures above are the more useful view of the risk. The national share is 6%, so this operation carries roughly 3.0 times the usual weather exposure. The split is drawn from 3,570 delay minutes reported on DL 2351.

Cancellations run at 2.59%, against 1.89% nationally. That is about 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 routes

What a delay on this flight costs

Badly late arrivals are rare here: only 4.4% land an hour or more behind schedule, against 8.3% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.

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.

Every one of the 348 flights under DL 2351 in the data flew DFW to BOS. 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. 348 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 DL 2351

For a booking, the cancellation rate is the figure to plan around on DL 2351: 2.59% of its 348 scheduled flights did not operate. A late arrival costs an hour and a half, but a cancellation costs the day, so leave a later option open.

Where to go next

A flight number here means Delta Air Lines’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 22 October 2026; recomputed monthly. How this data is collected.

Key figures