Flight number record

DL 1232

Delta Air Lines · Atlanta to Detroit

Route: ATL → DTW
Departs: 20:45
Flights: 275
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1232, check with Delta Air Lines.

DL 1232 draws a C+. About one flight in three arrives at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 275 flights, with a median arrival 2 minutes late.

The national on-time rate over the same period is 77.6%, so DL 1232 runs 12 points behind the country as a whole. Across a thousand flights that is about 120 extra late arrivals.

On time

65.6%

Arrivals under 15 minutes late, of 273 completed flights

Avg delay

56 min

Across delayed arrivals only, not all flights

Cancelled

0.73%

National rate is 1.81%

1 hour+ late

10.3%

National rate is 8.1%

These figures cover 275 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 1232 flies

DL 1232 flies ATL to DTW without a single fixed slot. Its most common scheduled departure was 20:45, used on 38 of 275 flights. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 20:4538 flights13.8%

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 20:45 departure sits in the 8pm–5am window. Across every US flight scheduled in that window the on-time rate is 70.5%, and DL 1232 runs 5 points worse at 65.6%. 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 1232 next to ATL to DTW

Every carrier on ATL to DTW combined arrived on time 78.0% of the time across 4,871 flights, so DL 1232 is 12 points behind it. Delta flew 3,698 flights on the same city pair under all its flight numbers, including this one, and those ran 79.5% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 16 points.

DL 1232 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 1232thin sample	275	65.6%	56 min	0.73%	C+
All Delta Air Lines on ATL–DTW	3,698	79.5%	57 min	0.51%	B+
All carriers on ATL–DTW	4,871	78.0%	63 min	0.82%	B+
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 1232 quarter by quarter

DL 1232 did not run the same all year. Its best quarter was Apr–Jun 2026 at 69.8% on time and its weakest Jul–Sep 2025 at 56.5%, a swing of 13 points on roughly 69 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 202546 flights56.5%
Oct–Dec 202563 flights67.7%
Jan–Mar 202680 flights64.6%
Apr–Jun 202686 flights69.8%

Scale runs 50% to 75%. Rows with fewer than 30 flights show a dash.

By weekday, DL 1232 did best on Tuesday at 82.9% on time and worst on Sunday at 48.9%. Each day rests on about 39 flights, so a gap of 34 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 1232 runs late

One category carries most of the weight here. Carrier accounts for 48% of the 5,249 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%
Late-arriving aircraft
30%
Extreme weather
12%
National Airspace System
10%

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 5,249 delay minutes reported on DL 1232.

Cancellations are rare at 0.73%, 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. 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.

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 275 flights under DL 1232 in the data flew ATL to DTW. 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. 275 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 1232

For a booking, DL 1232 is one of the weaker ways to fly ATL to DTW: 12 points below the route as a whole. If the schedule allows, compare it with the other departures listed on the route page before settling on this one.

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