Flight number record

DL 303

Delta Air Lines · Dallas-Fort Worth to Boston

Route: DFW → BOS
Departs: 18:59
Flights: 292
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 303, check with Delta Air Lines.

DL 303 sits in the middle of the pack with a C−. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.6%. The late ones land close to two hours behind schedule. That rests on 292 flights, with a median arrival 7 minutes early.

The national on-time rate over the same period is 77.6%, so DL 303 runs 4 points behind the country as a whole. Across a thousand flights that is about 43 extra late arrivals.

On time

73.3%

Arrivals under 15 minutes late, of 281 completed flights

Avg delay

100 min

Across delayed arrivals only, not all flights

Cancelled

3.77%

National rate is 1.81%

1 hour+ late

10.3%

National rate is 8.1%

These figures cover 292 flights between July 2025 and June 2026. Beyond the headline rate, 10.3% 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 DL 303 flies

DL 303 flies DFW to BOS without a single fixed slot. Its most common scheduled departure was 18:59, used on 91 of 292 flights, with 18:55 (88 flights) and 17:00 (46 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 18:5991 flights31.2%
Departs 18:5588 flights30.1%
Departs 17:0046 flights15.8%

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 18:59 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and DL 303 runs 5 points better at 73.3%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.

Against the route

DL 303 next to DFW to BOS

Every carrier on DFW to BOS combined arrived on time 67.1% of the time across 3,744 flights, so DL 303 is 6 points ahead of it. Delta flew 861 flights on the same city pair under all its flight numbers, including this one, and those ran 77.4% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 8 points.

DL 303 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 303thin sample	292	73.3%	100 min	3.77%	C−
All Delta Air Lines on DFW–BOS	861	77.4%	100 min	2.44%	B
All carriers on DFW–BOS	3,744	67.1%	76 min	3.21%	C−
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 303 quarter by quarter

DL 303 did not run the same all year. Its best quarter was Jan–Mar 2026 at 87.1% on time and its weakest Jul–Sep 2025 at 61.9%, a swing of 25 points on roughly 73 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 202567 flights61.9%
Oct–Dec 202573 flights67.6%
Jan–Mar 202674 flights87.1%
Apr–Jun 202678 flights75.3%

Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, DL 303 did best on Friday at 88.9% on time and worst on Tuesday at 64.6%. Each day rests on about 42 flights, so a gap of 24 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 303 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 7,515 reported delay minutes.

Late-arriving aircraft
36%
Carrier
34%
National Airspace System
18%
Extreme weather
12%

Extreme weather accounts for 12% 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 2.0 times the usual weather exposure. The split is drawn from 7,515 delay minutes reported on DL 303.

Cancellations run at 3.77%, against 1.81% nationally. That is about one flight in 25 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

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.3% 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 same number turns up on three other city pairs in the data, including BOS to DFW (182), MCO to LGA (4) and ATL to XNA (1), but none flew often enough under DL 303 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to DFW to BOS only.

One caution: this is a thin sample. 292 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 303

For a booking, the cancellation rate is the figure to plan around on DL 303: 3.77% of its 292 scheduled flights did not operate. A late arrival costs close to two hours, 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, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures