Flight number record

DL 1211

Delta Air Lines · Miami to Atlanta

Route: MIA → ATL
Departs: 07:05
Flights: 353
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1211, check with Delta Air Lines.

DL 1211 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 15 points better than the national rate of 77.6%. When something does go wrong the average delay runs an hour and a half. That rests on 353 flights, with a median arrival 8 minutes early.

Set against the rest of the country, DL 1211's record is 15 points better than the US average of 77.6%. That gap is worth roughly 146 fewer late arrivals for every thousand flights.

On time

92.2%

Arrivals under 15 minutes late, of 345 completed flights

Avg delay

93 min

Across delayed arrivals only, not all flights

Cancelled

1.98%

National rate is 1.81%

1 hour+ late

2.6%

National rate is 8.1%

These figures cover 353 flights between July 2025 and June 2026. The median arrival is 8 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.

Schedule

When DL 1211 flies

DL 1211 flies MIA to ATL without a single fixed slot. Its most common scheduled departure was 07:05, used on 67 of 353 flights, with 07:15 (61 flights) and 07:30 (52 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 07:0567 flights19.0%
Departs 07:1561 flights17.3%
Departs 07:3052 flights14.7%

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 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 1211 runs 3 points better at 92.2%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

DL 1211 next to MIA to ATL

Every carrier on MIA to ATL combined arrived on time 73.7% of the time across 6,223 flights, so DL 1211 is 19 points ahead of it. Delta flew 3,300 flights on the same city pair under all its flight numbers, including this one, and those ran 76.7% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 11 points.

DL 1211 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 1211thin sample	353	92.2%	93 min	1.98%	A
All Delta Air Lines on MIA–ATL	3,300	76.7%	83 min	1.39%	B
All carriers on MIA–ATL	6,223	73.7%	80 min	1.41%	C
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 1211 quarter by quarter

Quarter by quarter DL 1211 held fairly steady: 93.1% in Jul–Sep 2025, 88.9% in Oct–Dec 2025, 92.0% in Jan–Mar 2026 and 94.4% 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 202588 flights93.1%
Oct–Dec 202584 flights88.9%
Jan–Mar 202690 flights92.0%
Apr–Jun 202691 flights94.4%

Scale runs 80% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, DL 1211 ranged from 85.7% on Monday to 96.0% on Wednesday. With about 50 flights behind each day, a spread of 10 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why DL 1211 runs late

One category carries most of the weight here. Carrier accounts for 48% of the 2,511 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
28%
Late-arriving aircraft
22%
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 1,214 of the 2,511 delay minutes reported here. The split is drawn from 2,511 delay minutes reported on DL 1211.

Cancellations sit at 1.98% against a national 1.81%, which is ordinary. Diversions add another 0.28%.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 2.6% land an hour or more behind schedule, against 8.1% 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 594 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.

Every one of the 353 flights under DL 1211 in the data flew MIA 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. 353 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 1211

For a booking, read DL 1211 as 92.2% on time with 1.98% cancelled over 353 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