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DelayAtlas

Carrier performance at one airport

WNIND

Southwest Airlines at Indianapolis International

Departures
12,615
Period
June 2025 to May 2026
Routes
19
Rank here
#4 of 12
B+GRADE

Southwest Airlines at Indianapolis lands a B+, 2 points better than the national rate of 77.4%. About one flight in five arrive 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 12,615 flights, of which Delta Air Lines flew 4,504 at 88.4% on time.

Measured against the airport rather than the country, Southwest Airlines runs half a point behind the 79.9% weighted average across all carriers at IND. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.

Key figures

On time

79.4%

12,491 completed departures

Avg delay

55 min

Across delayed flights only

Cancelled

0.67%

At IND, this carrier only

Rank here

#4

Of 12 carriers clearing the floor at IND

These figures cover 13,000 flights between June 2025 and May 2026. The median arrival is 4 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.

Against the competition

Every carrier at IND, ranked

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 88.4% of the time; Allegiant Air manages 72.0%. Sample sizes sit next to every figure, because a two-point gap across 1,660 flights means less than a ten-point one.

On-time performance of all carriers departing IND
AirlineFlightsOn timeAvg delayCancelledGrade
Delta Air Lines4,50488.4%76 min1.22%A
Spirit Airlines1,54682.5%89 min2.98%B
Republic Airways13,58181.1%66 min2.94%B
Southwest Airlines (this page)12,61579.4%55 min0.67%B+
American Airlines6,76478.4%105 min2.20%B
Envoy Air70877.4%83 min1.55%B
United Airlines2,85377.3%75 min1.26%B
SkyWest Airlines2,01076.7%101 min2.69%B
Frontier Airlines1,00473.6%87 min1.59%C
PSA Airlines47872.9%117 min9.41%C−
Alaska Airlines56472.4%49 min1.42%C
Allegiant Air1,66072.0%78 min0.48%C+

PSA Airlines cancels 9.4% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.

Route by route

Where Southwest Airlines flies from IND

Southwest Airlines operates 19 routes out of IND with enough volume to report. Route records inside one carrier at one airport still spread widely, because a short shuttle and a transcontinental have very different exposure to a late inbound.

Southwest Airlines routes from IND
RouteFlightsOn timeAvg delayCancelledGrade
IND to MCO · Orlando1,60780.1%63 min0.93%B+
IND to DEN · Denver1,41075.3%54 min0.50%B+
IND to BWI · Baltimore1,21683.9%62 min1.64%B
IND to LAS · Las Vegas1,11778.8%50 min0.45%B+
IND to TPA · Tampa90575.3%60 min0.66%B+
IND to PHX · Phoenix90475.9%55 min0.22%B+
IND to RSW · Fort Myers81779.8%57 min0.86%B+
IND to DAL · Dallas67579.0%61 min1.04%B
IND to AUS · Austin66780.6%56 min0.15%B+
IND to MDW · Chicago61176.4%44 min0.82%B+
IND to HOU · Houston49286.9%55 min0.81%A+
IND to BNA · Nashville46480.9%52 min0.22%B+
IND to FLL · Fort Lauderdale41782.9%41 min0.72%B+
IND to MCI · Kansas Citythin sample35086.2%43 min0.57%A+
IND to ATL · Atlantathin sample33479.6%47 min0.00%B+
IND to SAN · San Diegothin sample27877.3%43 min0.00%B+
IND to SRQ · Sarasotathin sample19179.6%72 min0.00%B+
IND to MIA · Miamithin sample10874.1%46 min0.00%C+
IND to ECP · Panama Citythin sample4185.4%91 min0.00%A+

Departure window

Best time of day for this operation

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 36 points, against 16 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

  • 5am–8am3,578 flights93.3%
  • 8am–11am1,379 flights90.9%
  • 11am–2pm2,065 flights82.7%
  • 2pm–5pm2,184 flights71.4%
  • 5pm–8pm2,276 flights66.0%
  • 8pm–5am1,133 flights57.3%

Scale runs 50% to 100%. Rows with fewer than 30 flights show a dash.

The 8pm–5am window is where this operation falls apart: 57.3% on time, against 93.3% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in.

Across the year

Seasonal pattern

On-time rate by calendar month81J83F77M83A77M79J77J82A83S80O83N71D
Darker means more delays. Figures are on-time percentages.September best, December worst

December is the weak month at 70.9% on time, against 83.4% 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.

Delay causes

What holds this operation up

  • Late-arriving aircraft
    53%
  • National Airspace System
    23%
  • Carrier
    23%
  • Extreme weather
    2%
  • Security
    0%

53% 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 142,000 reported delay minutes here, that single category outweighs weather by 33 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.

Cancellations are rare at 0.67%, below the national 1.80% 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.

5.8% of arrivals land an hour or more late, close to the national 8.2%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route are the about an hour kind, which a normal layover absorbs.

12,615 flights sit behind these numbers, which is a large enough sample that the headline rate is not moving on noise. Where a sub-group falls below 30 flights the site shows a dash instead of a percentage.

Put together: the calendar is the biggest lever here, not the carrier or the hour. September runs 83.4% on time and December 70.9%, a swing of 13 points. If the dates move at all, move them out of December before you think about anything else.

Common questions

Southwest Airlines at IND

How often is Southwest Airlines at IND delayed?

About one flight in five arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 20.6% of the 12,615 flights in this analysis, against 22.6% nationally. Delayed flights are late by about an hour on average.

Which airline is most reliable on Southwest Airlines at IND?

Delta Air Lines leads at 88.4% on time across 4,504 flights. Allegiant Air is at the other end on 72.0%, a gap of 16 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.

What time of day has the fewest delays on Southwest Airlines at IND?

The 5am–8am departure window is the strongest at 93.3% on time. The 8pm–5am window is the weakest at 57.3%, 36 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 Southwest Airlines at IND?

December is the weakest month at 70.9% on time, compared with 83.4% in September. Across the year that is 13 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

Source: US DOT Bureau of Transportation Statistics, on-time performance data, June 2025 to May 2026. Updated monthly. How this data is collected.