Carrier route record

WNPIT→ATL

Southwest Airlines · Pittsburgh to Atlanta

Flights: 302
Period: July 2025 to June 2026
Share of route: 11%
Carriers: 2

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

Southwest on PIT to ATL earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 9 points better than the national rate of 77.6%. When something does go wrong the average delay runs roughly 40 minutes. That rests on 302 flights, with a median arrival 8 minutes early.

Set against the rest of the country, Southwest's PIT to ATL record is 9 points better than the US average of 77.6%. That gap is worth roughly 91 fewer late arrivals for every thousand flights.

On time

86.7%

Arrivals under 15 minutes late, of 300 completed flights

Avg delay

38 min

Across delayed arrivals only, not all flights

Cancelled

0.33%

National rate is 1.81%

Whole route

90.3%

Every carrier on PIT to ATL, 2,777 flights

These figures cover 302 flights between July 2025 and June 2026. The median arrival is 8 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 PIT to ATL

Southwest flew 302 of the 2,777 flights on PIT to ATL, about 11% of it. Its 86.7% on time is 4 points worse than the route as a whole, which runs 90.3%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from Delta at 90.7% to Southwest at 86.7%.

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 PIT to ATL
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	2,475	90.7%	71 min	2.34%	A
Southwest Airlines (this page)thin sample	302	86.7%	38 min	0.33%	A+

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–11am36 flights91.7%
11am–2pm198 flights91.3%
2pm–5pm17 flights—
5pm–8pm51 flights70.6%
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 91.7% of the time, against 70.6% for the evening 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 198 flights scheduled in it.

Across the year

Southwest on PIT to ATL through the year

Jul–Sep 202579 flights91.0%
Oct–Dec 202587 flights85.1%
Jan–Mar 202683 flights89.0%
Apr–Jun 202653 flights79.2%

Scale runs 70% to 95%. 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 86.7% on time across 302 flights.

Southwest on PIT to ATL did not run the same all year. Its best quarter was Jul–Sep 2025 at 91.0% on time and its weakest Apr–Jun 2026 at 79.2%, a swing of 12 points on roughly 76 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Across the week, Tuesday is the strongest day at 97.1% on time and Sunday the weakest at 72.5%. 25 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 55% of the 1,531 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
55%
Carrier
24%
National Airspace System
19%
Extreme weather
2%

55% 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 1,531 reported delay minutes here, that single category outweighs weather by 30 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 1,531 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 91.7% on time here.

Cancellations are rare at 0.33%, below the national 1.81% 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.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 1.3% 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 526 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg is a different operation and performs like one: it runs 81.7% on time across 302 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. 302 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 PIT to ATL

Put together: treat all of this as provisional. 302 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 86.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 300 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