Flight number record

DL 2599

Delta Air Lines · Atlanta to Madison

Route: ATL → MSN
Departs: 15:25
Flights: 326
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 2599, check with Delta Air Lines.

DL 2599 lands a B, 6 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That is a workable record, not a spotless one. That rests on 326 flights, with a median arrival 7 minutes early.

Set against the rest of the country, DL 2599's record is 6 points better than the US average of 77.6%. That gap is worth roughly 57 fewer late arrivals for every thousand flights.

On time

83.3%

Arrivals under 15 minutes late, of 318 completed flights

Avg delay

52 min

Across delayed arrivals only, not all flights

Cancelled

2.45%

National rate is 1.81%

1 hour+ late

4.7%

National rate is 8.1%

These figures cover 326 flights between July 2025 and June 2026. The median arrival is 7 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 2599 flies

DL 2599 flies ATL to MSN without a single fixed slot. Its most common scheduled departure was 15:25, used on 89 of 326 flights, with 15:15 (73 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 15:2589 flights27.3%
Departs 15:1573 flights22.4%

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 15:25 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and DL 2599 runs 11 points better at 83.3%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

DL 2599 next to ATL to MSN

Every carrier on ATL to MSN combined arrived on time 84.5% of the time across 1,025 flights, so DL 2599 is about level with it. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 2 points.

DL 2599 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 2599thin sample	326	83.3%	52 min	2.45%	B
All Delta Air Lines on ATL–MSN	1,025	84.5%	58 min	1.76%	B
All carriers on ATL–MSN	1,025	84.5%	58 min	1.76%	B
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 2599 quarter by quarter

Quarter by quarter DL 2599 held fairly steady: 81.8% in Jul–Sep 2025, 84.6% in Oct–Dec 2025, 82.1% in Jan–Mar 2026 and 85.2% in Apr–Jun 2026. A spread of 3 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202588 flights81.8%
Oct–Dec 202568 flights84.6%
Jan–Mar 202686 flights82.1%
Apr–Jun 202684 flights85.2%

Scale runs 75% to 90%. Rows with fewer than 30 flights show a dash.

By weekday, DL 2599 did best on Wednesday at 91.8% on time and worst on Thursday at 75.0%. Each day rests on about 47 flights, so a gap of 17 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 2599 runs late

One category carries most of the weight here. Carrier accounts for 58% of the 2,730 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
58%
Late-arriving aircraft
29%
National Airspace System
11%
Extreme weather
3%

The largest share of delay minutes, 58%, 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 1,570 of the 2,730 delay minutes reported here. The split is drawn from 2,730 delay minutes reported on DL 2599.

Cancellations sit at 2.45% against a national 1.81%, 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 4.7% 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 707 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.

DL 2599 is not only a ATL to MSN flight. It also flew MSN to ATL (283 flights, 87.2% on time) often enough to be scored on its own. Airlines attach one number to several legs of an aircraft's day, and each leg keeps its own record here, so check which city pair is on your booking before reading a rate.

One caution: this is a thin sample. 326 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.

Other routes flown as DL 2599
Also flown as	Flights	On time	Avg delay	Cancelled	Grade
MSN to ATLthin sample	283	87.2%	69 min	2.83%	A

What to do with this

Booking DL 2599

For a booking, read DL 2599 as 83.3% on time with 2.45% cancelled over 326 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