Flight number record
DL 303
Delta Air Lines · Dallas-Fort Worth to Boston
- Route
- DFW → BOS
- Departs
- 18:55
- Flights
- 251
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s DL 303, check with Delta Air Lines.
DL 303 lands a B−, about a point worse than the national rate of 77.3%. About one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That rests on 251 flights, with a median arrival 9 minutes early.
Key figures
On time
76.0%
Arrivals under 15 minutes late, of 242 completed flights
Avg delay
83 min
Across delayed arrivals only, not all flights
Cancelled
3.19%
National rate is 1.89%
1 hour+ late
9.5%
National rate is 8.3%
These figures cover 251 flights between September 2025 and August 2026. Beyond the headline rate, 9.5% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Schedule
When DL 303 flies
DL 303 flies DFW to BOS without a single fixed slot. Its most common scheduled departure was 18:55, used on 76 of 251 flights, with 18:59 (61 flights) and 17:00 (51 flights) next.
- Departs 18:5576 flights30.3%
- Departs 18:5961 flights24.3%
- Departs 17:0051 flights20.3%
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 18:55 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.0%, and DL 303 runs 8 points better at 76.0%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.
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Against the route
DL 303 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 303 is 9 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 trails by 5 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 303thin sample | 251 | 76.0% | 83 min | 3.19% | B− |
| 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 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 Oct–Dec 2025 at 67.6%, a swing of 20 points on roughly 84 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 202521 flights—
- Oct–Dec 202573 flights67.6%
- Jan–Mar 202674 flights87.1%
- Apr–Jun 202678 flights75.3%
- Jul–Sep 20265 flights—
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
By weekday, DL 303 did best on Friday at 92.3% on time and worst on Sunday at 63.9%. Each day rests on about 36 flights, so a gap of 28 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late DL 303 runs when it is late
DL 303 often beats the schedule: 78 of 242 completed flights, 32%, arrived 15 minutes or more early. The 58 late arrivals split 18 under half an hour, 17 between 30 and 60 minutes, and 23 an hour or more.
- 15+ min early78 flights32.2%
- Within 15 min106 flights43.8%
- 15–29 min late18 flights7.4%
- 30–59 min late17 flights7.0%
- 1–2 hours late10 flights4.1%
- 2+ hours late13 flights5.4%
Scale runs 0% to 100%.
Share of 242 completed flights by arrival against schedule.
8 of 55 late departures made up the time and arrived on time, 15% of them. 11 flights left on time and still arrived late.
The worst days
Worst days for DL 303
The latest arrival of the period was on 19 September 2025, 13 hours 5 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on three of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 19 September 2025 | 13 hours 5 minutes | Carrier |
| 28 April 2026 | 5 hours 21 minutes | Carrier |
| 10 May 2026 | 3 hours 57 minutes | Late-arriving aircraft |
| 14 October 2025 | 3 hours 1 minute | Late-arriving aircraft |
| 21 September 2025 | 2 hours 55 minutes | Carrier |
Delay causes
Why DL 303 runs late
Late-arriving aircraft accounts for 44% of the 4,783 delay minutes carriers reported here, and the remaining four split what is left.
- 44%Late-arriving aircraft
- 34%Carrier
- 19%National Airspace System
- 3%Extreme weather
44% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 4,783 reported delay minutes here, that single category outweighs weather by 15 to one. The split is drawn from 4,783 delay minutes reported on DL 303.
Cancellations run at 3.19%, against 1.89% nationally. That is about one flight in 30 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
9.5% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection 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 two other city pairs in the data, including BOS to DFW (185) and MCO to LGA (4), 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. 251 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: 3.19% of its 251 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.
Related
Where to go next
- DFW to BOS, every carrier and departure
- BOS to DFW, the return direction
- American Airlines 1206 on the same route82.6%
- Delta Air Lines 2351 on the same route88.2%
- American Airlines 2306 on the same route54.1%
- American Airlines 1366 on the same route61.8%
- Dallas/Fort Worth International (DFW) delay statistics
- Boston Logan International (BOS) delay statistics
- Delta Air Lines on-time record
- Every Delta Air Lines flight number with a record
- The most and least reliable flight numbers in the US
- Why the first flight of the morning is statistically safest
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 ; recomputed monthly. How this data is collected.