Carrier route record

WNRDU→ATL

Southwest Airlines · Raleigh to Atlanta

Flights: 247
Period: July 2025 to June 2026
Share of route: 5%
Carriers: 3

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

Southwest on RDU to ATL earns an 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 13 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 247 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 3,800 at 89.5% on time.

Set against the rest of the country, Southwest's RDU to ATL record is 13 points better than the US average of 77.6%. That gap is worth roughly 126 fewer late arrivals for every thousand flights.

On time

90.2%

Arrivals under 15 minutes late, of 245 completed flights

Avg delay

68 min

Across delayed arrivals only, not all flights

Cancelled

0.81%

National rate is 1.81%

Whole route

87.6%

Every carrier on RDU to ATL, 4,618 flights

These figures cover 247 flights between July 2025 and June 2026. The median arrival is 10 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 RDU to ATL

Southwest flew 247 of the 4,618 flights on RDU to ATL, about 5% of it. Its 90.2% on time is 3 points better than the route as a whole, which runs 87.6%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from Southwest at 90.2% to Frontier at 73.9%.

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 89.5% of the time; Frontier Airlines manages 73.9%. Sample sizes sit next to every figure, because a two-point gap across 571 flights means less than a ten-point one.

On-time performance by carrier on RDU to ATL
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines (this page)thin sample	247	90.2%	68 min	0.81%	A+
Delta Air Lines	3,800	89.5%	86 min	1.37%	A
Frontier Airlines	571	73.9%	95 min	2.80%	C

The spread between Delta and Frontier is 16 points, wide enough that it should decide the booking. On a hundred trips that is 16 more arrivals inside the on-time window.

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 14 points, against 16 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am40 flights100.0%
11am–2pm143 flights89.4%
2pm–5pm64 flights85.9%
5pm–8pm—
8pm–5am—

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 100.0% of the time, against 85.9% for the afternoon window. That is 14 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 143 flights scheduled in it.

Across the year

Southwest on RDU to ATL through the year

Jul–Sep 202592 flights92.4%
Oct–Dec 202592 flights87.0%
Jan–Mar 202663 flights91.8%

Scale runs 80% to 100%. 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 90.2% on time across 247 flights.

Quarter by quarter Southwest on RDU to ATL held fairly steady: 92.4% in Jul–Sep 2025, 87.0% in Oct–Dec 2025 and 91.8% in Jan–Mar 2026. A spread of 5 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Across the week, Wednesday is the strongest day at 94.4% on time and Sunday the weakest at 76.5%. 18 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 49% of the 1,625 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
49%
National Airspace System
30%
Carrier
21%

49% 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 1,625 reported delay minutes here, that single category outweighs weather by 49 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 1,625 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 100.0% on time here.

Cancellations are rare at 0.81%, 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 3.3% 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.

At 356 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 83.6% on time across 247 flights, 7 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 7 points of difference.

One caution: this is a thin sample. 247 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 RDU to ATL

Put together: treat all of this as provisional. 247 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 90.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 245 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