Flight number record

DL 921

Delta Air Lines · Atlanta to Dallas-Fort Worth

Route: ATL → DFW
Departs: 13:59
Flights: 363
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 921, check with Delta Air Lines.

DL 921 sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 363 flights, with a median arrival 3 minutes early.

On time

74.4%

Arrivals under 15 minutes late, of 360 completed flights

Avg delay

68 min

Across delayed arrivals only, not all flights

Cancelled

0.83%

National rate is 1.81%

1 hour+ late

9.4%

National rate is 8.1%

These figures cover 363 flights between July 2025 and June 2026. Beyond the headline rate, 9.4% 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 921 flies

DL 921 flies ATL to DFW without a single fixed slot. Its most common scheduled departure was 13:59, used on 81 of 363 flights, with 13:41 (71 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 13:5981 flights22.3%
Departs 13:4171 flights19.6%

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 13:59 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.8%, and DL 921 runs 4 points worse at 74.4%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

DL 921 next to ATL to DFW

Every carrier on ATL to DFW combined arrived on time 74.3% of the time across 6,698 flights, so DL 921 is about level with it. Delta flew 2,791 flights on the same city pair under all its flight numbers, including this one, and those ran 75.4% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 7 points.

DL 921 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 921thin sample	363	74.4%	68 min	0.83%	C+
All Delta Air Lines on ATL–DFW	2,791	75.4%	57 min	2.51%	B
All carriers on ATL–DFW	6,698	74.3%	80 min	2.76%	C
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 921 quarter by quarter

Quarter by quarter DL 921 held fairly steady: 72.8% in Jul–Sep 2025, 76.9% in Oct–Dec 2025, 77.0% in Jan–Mar 2026 and 71.1% in Apr–Jun 2026. A spread of 6 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights72.8%
Oct–Dec 202591 flights76.9%
Jan–Mar 202689 flights77.0%
Apr–Jun 202691 flights71.1%

Scale runs 65% to 80%. Rows with fewer than 30 flights show a dash.

By weekday, DL 921 did best on Thursday at 90.4% on time and worst on Wednesday at 67.3%. Each day rests on about 52 flights, so a gap of 23 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 921 runs late

One category carries most of the weight here. Carrier accounts for 48% of the 6,245 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

Carrier
48%
National Airspace System
35%
Late-arriving aircraft
16%
Extreme weather
2%

The largest share of delay minutes, 48%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 2,967 of the 6,245 delay minutes reported here. The split is drawn from 6,245 delay minutes reported on DL 921.

Cancellations are rare at 0.83%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

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. 9.4% 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.

The 731 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The same number turns up on one other city pair in the data, including DFW to ATL (45), but none flew often enough under DL 921 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to ATL to DFW only.

One caution: this is a thin sample. 363 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 921

For a booking, read DL 921 as 74.4% on time with 0.83% cancelled over 363 flights. Those are rates from the past twelve months, not a forecast for any particular day.

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