Carrier route record

WNRDU→BNA

Southwest Airlines · Raleigh to Nashville

Flights: 1,259
Period: July 2025 to June 2026
Share of route: 57%
Carriers: 2

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

Southwest on RDU to BNA lands a B, 4 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 50 minutes on average. That is a workable record, not a spotless one. That rests on 1,259 flights, with a median arrival 5 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate Southwest on RDU to BNA from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

81.3%

Arrivals under 15 minutes late, of 1,245 completed flights

Avg delay

49 min

Across delayed arrivals only, not all flights

Cancelled

1.03%

National rate is 1.81%

Whole route

80.3%

Every carrier on RDU to BNA, 2,213 flights

These figures cover 1,259 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 RDU to BNA

Southwest flew 1,259 of the 2,213 flights on RDU to BNA, most of the route. Its 81.3% on time is about level with the route as a whole at 80.3%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from Southwest at 81.3% to Republic at 78.9%.

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 RDU to BNA
Airline	Flights	On time	Avg delay	Cancelled	Grade
Southwest Airlines (this page)	1,259	81.3%	49 min	1.03%	B
Republic Airways	954	78.9%	73 min	2.20%	B

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 36 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–8am365 flights96.4%
8am–11am152 flights94.7%
11am–2pm187 flights84.4%
2pm–5pm172 flights65.7%
5pm–8pm203 flights73.0%
8pm–5am180 flights60.2%

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

The 8pm–5am window is where this operation falls apart: 60.2% on time, against 96.4% 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. The 5am–8am window is the busiest, with 365 flights scheduled in it.

Across the year

Southwest on RDU to BNA through the year

Darker means more delays. Figures are on-time percentages.February best, May worst

Delays peak in May, when the on-time rate falls to 70.0%. February is the strongest month at 93.9%. Moving a flexible trip across that boundary buys 24 points. December was the busiest month here, with 116 flights.

Across the week, Wednesday is the strongest day at 87.9% on time and Thursday the weakest at 76.3%. 12 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 62% of the 11,000 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
62%
Carrier
23%
National Airspace System
11%
Extreme weather
2%
Security
2%

62% 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 11,000 reported delay minutes here, that single category outweighs weather by 32 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 11,322 reported delay minutes.

The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 96.4% on time here.

Cancellations sit at 1.03% against a national 1.81%, which is ordinary. Diversions add another 0.08%.

Connections and stage length

What a delay here costs

Badly late arrivals are rare here: only 4.5% 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 442 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 5am–8am window matters as much as it does.

The return leg is a different operation and performs like one: it runs 75.5% on time across 1,261 flights, 6 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 6 points of difference.

The sample behind these figures is 1,259 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.

What to do with this

Booking Southwest on RDU to BNA

Put together: the calendar is the biggest lever here, not the carrier or the hour. February runs 93.9% on time and May 70.0%, a swing of 24 points. If the dates move at all, move them out of May before you think about anything else. 1,245 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