Carrier performance at one airport
WN→CMH
Southwest Airlines at John Glenn Columbus International
- Departures
- 12,338
- Period
- September 2025 to August 2026
- Routes
- 19
- Rank here
- #5 of 11
Southwest Airlines at Columbus lands a B, 3 points better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That rests on 12,338 flights, of which Delta Air Lines flew 3,730 at 87.1% on time.
Measured against the airport rather than the country, Southwest Airlines runs half a point behind the 80.4% weighted average across all carriers at CMH. That is the comparison worth making: every operator here works the same runways, the same airspace and the same weather.
Key figures
On time
80.0%
12,168 completed departures
Avg delay
59 min
Across delayed flights only
Cancelled
1.01%
At CMH, this carrier only
Rank here
#5
Of 11 carriers clearing the floor at CMH
These figures cover 12,000 flights between September 2025 and August 2026. The median arrival is 6 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 CMH, ranked
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 87.1% of the time; Frontier Airlines manages 66.4%. Sample sizes sit next to every figure, because a two-point gap across 567 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 3,730 | 87.1% | 86 min | 1.21% | A |
| American Airlines | 4,222 | 82.4% | 113 min | 2.13% | B |
| Republic Airways | 13,053 | 82.3% | 67 min | 3.45% | B− |
| Envoy Air | 3,078 | 80.9% | 90 min | 1.10% | B |
| Southwest Airlines (this page) | 12,338 | 80.0% | 59 min | 1.01% | B |
| SkyWest Airlines | 1,458 | 76.5% | 120 min | 3.02% | B− |
| PSA Airlines | 1,643 | 76.0% | 87 min | 4.50% | B− |
| United Airlines | 3,396 | 74.1% | 87 min | 1.33% | C |
| Spirit Airlines | 859 | 72.8% | 82 min | 3.84% | C− |
| Alaska Airlines | 465 | 70.9% | 50 min | 1.08% | C |
| Frontier Airlines | 567 | 66.4% | 84 min | 1.94% | C |
PSA Airlines cancels 4.5% 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 CMH
Southwest Airlines operates 19 routes out of CMH 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.
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| CMH to MCO · Orlando | 1,510 | 79.4% | 65 min | 1.13% | B |
| CMH to MDW · Chicago | 1,237 | 79.7% | 56 min | 1.62% | B |
| CMH to BNA · Nashville | 1,046 | 82.6% | 50 min | 0.57% | B+ |
| CMH to BWI · Baltimore | 1,044 | 87.2% | 71 min | 1.53% | A |
| CMH to DEN · Denver | 923 | 78.8% | 68 min | 0.54% | B+ |
| CMH to TPA · Tampa | 906 | 83.8% | 52 min | 1.21% | B |
| CMH to LAS · Las Vegas | 842 | 79.1% | 59 min | 0.36% | B+ |
| CMH to STL · St. Louis | 674 | 83.3% | 65 min | 0.59% | B+ |
| CMH to RSW · Fort Myers | 654 | 79.2% | 66 min | 1.68% | B |
| CMH to DAL · Dallas | 551 | 79.3% | 46 min | 1.45% | B |
| CMH to PHX · Phoenix | 531 | 80.2% | 49 min | 1.13% | B |
| CMH to FLL · Fort Lauderdale | 374 | 79.8% | 52 min | 0.80% | B+ |
| CMH to AUS · Austin | 368 | 83.1% | 53 min | 0.27% | B+ |
| CMH to HOU · Houstonthin sample | 354 | 79.3% | 63 min | 0.28% | B+ |
| CMH to DCA · Washingtonthin sample | 350 | 57.9% | 67 min | 1.14% | D |
| CMH to ATL · Atlantathin sample | 309 | 80.7% | 48 min | 0.97% | B+ |
| CMH to SRQ · Sarasotathin sample | 229 | 75.2% | 64 min | 1.31% | B |
| CMH to SAN · San Diegothin sample | 212 | 63.2% | 40 min | 0.47% | D+ |
| CMH to MIA · Miamithin sample | 160 | 78.5% | 46 min | 1.25% | B |
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 29 points, against 21 points between the best and worst carrier.
- 5am–8am3,327 flights94.7%
- 8am–11am1,453 flights90.3%
- 11am–2pm2,132 flights80.2%
- 2pm–5pm2,190 flights69.5%
- 5pm–8pm2,286 flights67.7%
- 8pm–5am950 flights66.1%
Scale runs 60% to 100%.
Book the early departure. Flights leaving between 5am–8am arrive on time 94.7% of the time, against 66.1% for the overnight window. That is 29 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 3,327 flights scheduled in it.
Across the year
Seasonal pattern
August is the worst month at 73.9% on time, 14 points below September, the best at 87.8%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. March was the busiest month here, with 1,224 flights.
Delay causes
What holds this operation up
- 51%Late-arriving aircraft
- 25%Carrier
- 23%National Airspace System
- 1%Extreme weather
- 0%Security
51% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 142,000 reported delay minutes here, that single category outweighs weather by 35 to one. The split is drawn from 142,460 reported delay minutes.
Cancellations sit at 1.01% against a national 1.89%, which is ordinary. Diversions add another 0.36%.
5.9% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last about an hour, which a normal layover absorbs.
12,338 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 87.8% on time and August 73.9%, a swing of 14 points. If the dates move at all, move them out of August before you think about anything else. 12,168 completed flights over 12 months sit behind that.
Common questions
Southwest Airlines at CMH
How often is Southwest Airlines at CMH delayed?
About one flight in five arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 20.0% of the 12,338 flights in this analysis, against 22.7% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on Southwest Airlines at CMH?
Delta Air Lines leads at 87.1% on time across 3,730 flights. Frontier Airlines is at the other end on 66.4%, a gap of 21 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 CMH?
The 5am–8am departure window is the strongest at 94.7% on time. The 8pm–5am window is the weakest at 66.1%, 29 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 August delays on Southwest Airlines at CMH?
August is the weakest month at 73.9% on time, compared with 87.8% in September. Across the year that is 14 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
- Southwest Airlines network-wide record
- John Glenn Columbus International (CMH) all carriers
- CMH to MCO route record79.4%
- CMH to MDW route record79.7%
- CMH to BNA route record82.6%
- CMH to BWI route record87.2%
- Do airlines run better at their own hubs?
- Why the first flight of the morning is statistically safest
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.