Carrier route record

WNCMH→ATL

Southwest Airlines · Columbus to Atlanta

Flights: 326
Period: July 2025 to June 2026
Share of route: 10%
Carriers: 4

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.

Southwest on CMH to ATL lands a B+, 4 points better than the national rate of 77.6%. Roughly one flight in five arrives 15 minutes late or worse, and those flights are late by about 45 minutes on average. That is a workable record, not a spotless one. That rests on 326 flights, with a median arrival 5 minutes early.

Set against the rest of the country, Southwest's CMH to ATL record is 4 points better than the US average of 77.6%. That gap is worth roughly 41 fewer late arrivals for every thousand flights.

On time

81.7%

Arrivals under 15 minutes late, of 323 completed flights

Avg delay

46 min

Across delayed arrivals only, not all flights

Cancelled

0.92%

National rate is 1.81%

Whole route

85.9%

Every carrier on CMH to ATL, 3,160 flights

These figures cover 326 flights between July 2025 and June 2026. The median arrival is 5 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

Southwest against every carrier on CMH to ATL

Southwest flew 326 of the 3,160 flights on CMH to ATL, about 10% of it. Its 81.7% on time is 4 points worse than the route as a whole, which runs 85.9%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from Delta at 88.2% to Frontier at 51.1%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.

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.

On-time performance by carrier on CMH to ATL
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	2,693	88.2%	92 min	1.56%	A
Spirit Airlinesthin sample	7	85.7%	206 min	0.00%	A+
Southwest Airlines (this page)thin sample	326	81.7%	46 min	0.92%	B+
Frontier Airlinesthin sample	134	51.1%	65 min	2.24%	F

Departure window

When Southwest runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 21 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–8am—
8am–11am72 flights88.7%
11am–2pm202 flights83.0%
2pm–5pm47 flights68.1%
5pm–8pm5 flights—
8pm–5am—

Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.

Book the morning departure. Flights leaving between 8am–11am arrive on time 88.7% of the time, against 68.1% for the afternoon window. That is 21 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 202 flights scheduled in it.

Across the year

Southwest on CMH to ATL through the year

Jul–Sep 202592 flights83.7%
Oct–Dec 202591 flights79.1%
Jan–Mar 202683 flights85.0%
Apr–Jun 202660 flights78.3%

Scale runs 70% to 90%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 81.7% on time across 326 flights.

Quarter by quarter Southwest on CMH to ATL held fairly steady: 83.7% in Jul–Sep 2025, 79.1% in Oct–Dec 2025, 85.0% in Jan–Mar 2026 and 78.3% 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.

Across the week, Tuesday is the strongest day at 95.0% on time and Sunday the weakest at 70.6%. 24 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Southwest runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 67% of the 2,697 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
67%
Carrier
20%
National Airspace System
13%
Extreme weather
1%

67% 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 2,697 reported delay minutes here, that single category outweighs weather by 67 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 2,697 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 88.7% on time here.

Cancellations sit at 0.92% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 3.1% 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 447 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 76.5% on time across 326 flights, 5 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 5 points of difference.

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.

What to do with this

Booking Southwest on CMH to ATL

Put together: treat all of this as provisional. 326 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 81.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 323 completed flights over 12 months sit behind that.

Where to go next

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