Route reliability record
IND→ATL
Indianapolis to Atlanta
- Flights
- 3,187
- Period
- July 2025 to June 2026
- Distance
- 432 mi
- Carriers
- 5
This route earns a 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 11 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 3,187 flights, with a median arrival 14 minutes early.
Set against the rest of the country, this route's record is 11 points better than the US average of 77.6%. That gap is worth roughly 109 fewer late arrivals for every thousand flights.
Key figures
On time
88.5%
Arrivals under 15 minutes late, of 3,134 completed flights
Avg delay
72 min
Across delayed arrivals only, not all flights
Cancelled
1.32%
National rate is 1.81%
Best carrier
Delta
90.8% on time across 2,710 flights
These figures cover 3,187 flights between July 2025 and June 2026. The median arrival is 14 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.
Carrier by carrier
Which airline is most reliable on IND to ATL
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| American Airlinesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| Delta Air Lines | 2,710 | 90.8% | 78 min | 1.44% | A |
| Southwest Airlinesthin sample | 328 | 79.5% | 51 min | 0.00% | B+ |
| Spirit Airlinesthin sample | 7 | 71.4% | 169 min | 0.00% | C+ |
| Frontier Airlinesthin sample | 141 | 65.2% | 71 min | 2.13% | C |
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 15 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am713 flights93.6%
- 8am–11am535 flights95.6%
- 11am–2pm737 flights87.3%
- 2pm–5pm651 flights84.1%
- 5pm–8pm446 flights81.1%
- 8pm–5am105 flights84.5%
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 95.6% of the time, against 81.1% for the evening window. That is 15 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 11am–2pm window is the busiest, with 737 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 18 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
December is the weak month at 77.1% on time, against 94.6% in September. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. July was the busiest month here, with 303 flights.
Across the week, Tuesday is the strongest day at 90.7% on time and Monday the weakest at 83.9%. 7 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Late-arriving aircraft accounts for 44% of the 26,000 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.
- 44%Late-arriving aircraft
- 32%Carrier
- 19%National Airspace System
- 5%Extreme weather
44% 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 26,000 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 26,066 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 95.6% on time here.
Cancellations sit at 1.32% against a national 1.81%, which is ordinary. Diversions add another 0.35%.
Connections and stage length
What a delay here actually costs
Badly late arrivals are rare here: only 3.7% 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.
At 432 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8am–11am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 82.7% on time across 3,190 flights, 6 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 6 points of difference.
The sample behind these figures is 3,187 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 94.6% on time and December 77.1%, a swing of 18 points. If the dates move at all, move them out of December before you think about anything else. 3,134 completed flights over 12 months sit behind that.
Common questions
IND to ATL questions
How often is IND to ATL delayed?
About one flight in nine arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 11.5% of the 3,187 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.
How reliable is IND to ATL compared with the rest of the country?
88.5% of flights arrive on time here against a national 77.6%, a difference of 11 points in its favour. That is worth a A on this site's grading scale.
What time of day has the fewest delays on IND to ATL?
The 8am–11am departure window is the strongest at 95.6% on time. The 5pm–8pm window is the weakest at 81.1%, 15 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are December delays on IND to ATL?
December is the weakest month at 77.1% on time, compared with 94.6% in September. Across the year that is 18 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- ATL to IND — the return legseparate record
- Indianapolis International (IND) delay statistics
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- American Airlines on-time record100.0%
- Delta Air Lines on-time record90.8%
- Southwest Airlines on-time record79.5%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Direction matters. IND to ATL and ATL to IND are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.