Flight number record

DL 3125

Delta Air Lines · Indianapolis to Atlanta

Route: IND → ATL
Departs: 10:04
Flights: 260
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 3125, check with Delta Air Lines.

DL 3125 earns an A−. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 18 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 45 minutes. That rests on 260 flights, with a median arrival 16 minutes early.

Set against the rest of the country, DL 3125's record is 18 points better than the US average of 77.6%. That gap is worth roughly 180 fewer late arrivals for every thousand flights.

On time

95.6%

Arrivals under 15 minutes late, of 250 completed flights

Avg delay

47 min

Across delayed arrivals only, not all flights

Cancelled

3.85%

National rate is 1.81%

1 hour+ late

0.8%

National rate is 8.1%

These figures cover 260 flights between July 2025 and June 2026. The median arrival is 16 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 3125 flies

DL 3125 flies IND to ATL without a single fixed slot. Its most common scheduled departure was 10:04, used on 50 of 260 flights, with 10:10 (34 flights) and 10:00 (31 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 10:0450 flights19.2%
Departs 10:1034 flights13.1%
Departs 10:0031 flights11.9%

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 10:04 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and DL 3125 runs 12 points better at 95.6%. 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 3125 next to IND to ATL

Every carrier on IND to ATL combined arrived on time 88.5% of the time across 3,187 flights, so DL 3125 is 7 points ahead of it. Delta flew 2,710 flights on the same city pair under all its flight numbers, including this one, and those ran 90.8% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 14 points.

DL 3125 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 3125thin sample	260	95.6%	47 min	3.85%	A−
All Delta Air Lines on IND–ATL	2,710	90.8%	78 min	1.44%	A
All carriers on IND–ATL	3,187	88.5%	72 min	1.32%	A
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 3125 quarter by quarter

Quarter by quarter DL 3125 held fairly steady: 96.7% in Jul–Sep 2025, 95.6% in Oct–Dec 2025, 91.4% in Jan–Mar 2026 and 98.4% in Apr–Jun 2026. A spread of 7 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202560 flights96.7%
Oct–Dec 202570 flights95.6%
Jan–Mar 202660 flights91.4%
Apr–Jun 202670 flights98.4%

Scale runs 85% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, DL 3125 ranged from 91.7% on Sunday to 97.6% on Tuesday. With about 37 flights behind each day, a spread of 6 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why DL 3125 runs late

One category carries most of the weight here. Late-arriving aircraft accounts for 74% of the 513 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.

Late-arriving aircraft
74%
National Airspace System
14%
Extreme weather
9%
Carrier
3%

74% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 513 reported delay minutes here, that single category outweighs weather by 8 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 513 delay minutes reported on DL 3125.

Cancellations run at 3.85%, against 1.81% nationally. That is about one flight in 25 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 0.8% 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 same number turns up on one other city pair in the data, including ATL to IND (248), but none flew often enough under DL 3125 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to IND to ATL only.

One caution: this is a thin sample. 260 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 3125

For a booking, the cancellation rate is the figure to plan around on DL 3125: 3.85% of its 260 scheduled flights did not operate. A late arrival costs roughly 45 minutes, but a cancellation costs the day, so leave a later option open.

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