Carrier route record
WNDCA→BNA
Southwest Airlines · Washington to Nashville
- Flights
- 1,653
- Period
- July 2025 to June 2026
- Share of route
- 38%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on DCA to BNA sits in the middle of the pack with a B. Close to three flights in four arrive on time by the DOT's definition, 2 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 1,653 flights. The strongest carrier on the route with a full sample, Republic Airways, flew 1,861 at 83.5% on time.
The US average over the same twelve months is 77.6%, so there is little to separate Southwest on DCA to BNA from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
75.9%
Arrivals under 15 minutes late, of 1,615 completed flights
Avg delay
63 min
Across delayed arrivals only, not all flights
Cancelled
2.00%
National rate is 1.81%
Whole route
77.1%
Every carrier on DCA to BNA, 4,329 flights
These figures cover 1,653 flights between July 2025 and June 2026. Beyond the headline rate, 8.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Southwest against every carrier on DCA to BNA
Southwest flew 1,653 of the 4,329 flights on DCA to BNA, about 38% of it. Its 75.9% on time is about level with the route as a whole at 77.1%. Ranked by on-time rate it is number two of five carriers on the route, where the range runs from Republic at 83.5% to PSA at 59.2%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. Republic Airways arrives on time 83.5% of the time; PSA Airlines manages 59.2%. Sample sizes sit next to every figure, because a two-point gap across 387 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airways | 1,861 | 83.5% | 61 min | 2.26% | B |
| Southwest Airlines (this page) | 1,653 | 75.9% | 63 min | 2.00% | B |
| Envoy Airthin sample | 115 | 75.7% | 65 min | 0.00% | B+ |
| American Airlinesthin sample | 313 | 65.5% | 75 min | 5.43% | C− |
| PSA Airlines | 387 | 59.2% | 78 min | 10.08% | D− |
PSA Airlines cancels 10.1% 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.
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 48 points, against 24 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am365 flights95.3%
- 8am–11am312 flights79.9%
- 11am–2pm289 flights74.2%
- 2pm–5pm266 flights68.0%
- 5pm–8pm369 flights63.5%
- 8pm–5am52 flights47.8%
Scale runs 40% to 100%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 47.8% on time, against 95.3% 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 5pm–8pm window is the busiest, with 369 flights scheduled in it.
Across the year
Southwest on DCA to BNA through the year
Delays peak in May, when the on-time rate falls to 58.8%. January is the strongest month at 90.4%. Moving a flexible trip across that boundary buys 32 points. October was the busiest month here, with 153 flights.
Across the week, Tuesday is the strongest day at 82.3% on time and Friday the weakest at 69.3%. 13 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 60% of the 24,000 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.
- 60%Late-arriving aircraft
- 22%Carrier
- 17%National Airspace System
- 1%Extreme weather
- 0%Security
60% 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 24,000 reported delay minutes here, that single category outweighs weather by 60 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 24,386 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 95.3% on time here.
Cancellations sit at 2.00% against a national 1.81%, which is ordinary. Diversions add another 0.30%.
Connections and stage length
What a delay here costs
8.5% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says 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.
The 562 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 72.2% on time across 1,653 flights, 4 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 4 points of difference.
The sample behind these figures is 1,653 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 DCA to BNA
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 90.4% on time and May 58.8%, a swing of 32 points. If the dates move at all, move them out of May before you think about anything else. 1,615 completed flights over 12 months sit behind that.
Related
Where to go next
- DCA to BNA, every carrier
- Southwest on BNA to DCA, the return leg
- Republic Airways on DCA to BNA83.5%
- Envoy Air on DCA to BNA75.7%
- American Airlines on DCA to BNA65.5%
- PSA Airlines on DCA to BNA59.2%
- Southwest Airlines network-wide record
- Ronald Reagan Washington National (DCA) delay statistics
- Nashville International (BNA) delay statistics
- Same route, different airline: where the carrier you pick matters most
- Why the first flight of the morning is statistically safest
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.