Flight number record
DL 923
Delta Air Lines · Boston to Atlanta
- Route
- BOS → ATL
- Departs
- 06:55
- Flights
- 342
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s DL 923, check with Delta Air Lines.
DL 923 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 10 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 342 flights, with a median arrival 13 minutes early.
Set against the rest of the country, DL 923's record is 10 points better than the US average of 77.3%. That gap is worth roughly 99 fewer late arrivals for every thousand flights.
Key figures
On time
87.2%
Arrivals under 15 minutes late, of 337 completed flights
Avg delay
94 min
Across delayed arrivals only, not all flights
Cancelled
1.46%
National rate is 1.89%
1 hour+ late
3.6%
National rate is 8.3%
These figures cover 342 flights between September 2025 and August 2026. The median arrival is 13 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.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Schedule
When DL 923 flies
DL 923 flies BOS to ATL without a single fixed slot. Its most common scheduled departure was 06:55, used on 63 of 342 flights, with 06:45 (59 flights) and 08:00 (58 flights) next.
- Departs 06:5563 flights18.4%
- Departs 06:4559 flights17.3%
- Departs 08:0058 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 06:55 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and DL 923 runs 2 points worse at 87.2%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Against the route
DL 923 next to BOS to ATL
Every carrier on BOS to ATL combined arrived on time 76.8% of the time across 5,050 flights, so DL 923 is 10 points ahead of it. Delta flew 3,726 flights on the same city pair under all its flight numbers, including this one, and those ran 80.8% on time. Across its whole network Delta Air Lines managed 81.1%, which this flight beats by 6 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 923thin sample | 342 | 87.2% | 94 min | 1.46% | A |
| All Delta Air Lines on BOS–ATL | 3,726 | 80.8% | 75 min | 1.85% | B |
| All carriers on BOS–ATL | 5,050 | 76.8% | 72 min | 2.24% | B |
| Delta Air Lines, whole network | 1,039,517 | 81.1% | 71 min | 1.74% | B |
Across the year
DL 923 quarter by quarter
Quarter by quarter DL 923 held fairly steady: 81.4% in Oct–Dec 2025, 87.8% in Jan–Mar 2026, 90.1% in Apr–Jun 2026 and 90.2% in Jul–Sep 2026. A spread of 9 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.
- Jul–Sep 202517 flights—
- Oct–Dec 202586 flights81.4%
- Jan–Mar 202686 flights87.8%
- Apr–Jun 202691 flights90.1%
- Jul–Sep 202662 flights90.2%
Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.
By weekday, DL 923 did best on Saturday at 97.6% on time and worst on Tuesday at 79.6%. Each day rests on about 49 flights, so a gap of 18 points is worth noticing but could still narrow in another year.
Arrival by arrival
How late DL 923 runs when it is late
DL 923 often beats the schedule: 154 of 337 completed flights, 46%, arrived 15 minutes or more early. The 43 late arrivals split 21 under half an hour, 10 between 30 and 60 minutes, and 12 an hour or more.
- 15+ min early154 flights45.7%
- Within 15 min140 flights41.5%
- 15–29 min late21 flights6.2%
- 30–59 min late10 flights3.0%
- 1–2 hours late6 flights1.8%
- 2+ hours late6 flights1.8%
Scale runs 0% to 100%.
Share of 337 completed flights by arrival against schedule.
12 of 41 late departures made up the time and arrived on time, 29% of them. 14 flights left on time and still arrived late.
The worst days
Worst days for DL 923
The latest arrival of the period was on 26 December 2025, 17 hours 4 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. On three of the five worst days the largest share was filed as carrier-caused (crew, maintenance, fuelling, baggage).
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 26 December 2025 | 17 hours 4 minutes | Late-arriving aircraft |
| 30 October 2025 | 14 hours 10 minutes | Carrier |
| 10 November 2025 | 4 hours 32 minutes | Carrier |
| 9 June 2026 | 3 hours 38 minutes | Carrier |
| 27 January 2026 | 3 hours 4 minutes | National Airspace System |
Delay causes
Why DL 923 runs late
Carrier accounts for 57% of the 4,052 delay minutes carriers reported here, and the remaining four split what is left.
- 57%Carrier
- 25%Late-arriving aircraft
- 17%National Airspace System
- 1%Extreme weather
The largest share of delay minutes, 57%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 2,321 of the 4,052 delay minutes reported here. The split is drawn from 4,052 delay minutes reported on DL 923.
Cancellations sit at 1.46% against a national 1.89%, which is ordinary. Diversions add another 0.00%.
Connections and routes
What a delay on this flight costs
Badly late arrivals are rare here: only 3.6% 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.
The 946 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.
Every one of the 342 flights under DL 923 in the data flew BOS to ATL. 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. 342 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 923
For a booking, DL 923 has one of the better records a US domestic flight can show: 87.2% on time and 1.46% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- BOS to ATL, every carrier and departure
- ATL to BOS, the return direction
- Delta Air Lines 695 on the same route86.0%
- Delta Air Lines 322 on the same route78.0%
- Delta Air Lines 973 on the same route79.1%
- Delta Air Lines 456 on the same route89.4%
- Delta Air Lines 385 on the same route86.4%
- Delta Air Lines 2464 on the same route74.9%
- Boston Logan International (BOS) delay statistics
- Hartsfield-Jackson Atlanta International (ATL) 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
- How to read this site: grades, sample sizes, and honest caveats
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.