Carrier route record
WNLAS→BWI
Southwest Airlines · Las Vegas to Baltimore
- Flights
- 1,630
- Period
- September 2025 to August 2026
- Share of route
- 94%
- Carriers
- 2
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on LAS to BWI lands a B, about a point better than the national rate of 77.3%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about 45 minutes on average. That rests on 1,630 flights, with a median arrival 3 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate Southwest on LAS to BWI from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
78.6%
Arrivals under 15 minutes late, of 1,599 completed flights
Avg delay
45 min
Across delayed arrivals only, not all flights
Cancelled
1.10%
National rate is 1.89%
Whole route
78.9%
Every carrier on LAS to BWI, 1,743 flights
These figures cover 1,630 flights between September 2025 and August 2026. The median arrival is 3 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.
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Carrier by carrier
Southwest against every carrier on LAS to BWI
Southwest flew 1,630 of the 1,743 flights on LAS to BWI, most of the route. Its 78.6% on time is about level with the route as a whole at 78.9%. Ranked by on-time rate it is last of two carriers on the route, where the range runs from Spirit at 82.3% to Southwest at 78.6%. One 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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 113 | 82.3% | 101 min | 0.00% | B+ |
| Southwest Airlines (this page) | 1,630 | 78.6% | 45 min | 1.10% | B |
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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 33 points, against half a point between the best and worst carrier.
- 5am–8am365 flights92.8%
- 8am–11am230 flights82.3%
- 11am–2pm247 flights69.1%
- 2pm–5pm367 flights59.8%
- 5pm–8pm56 flights61.8%
- 8pm–5am365 flights89.5%
Scale runs 50% to 100%.
Book the early departure. Flights leaving between 5am–8am arrive on time 92.8% of the time, against 59.8% for the afternoon window. That is 33 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 367 flights scheduled in it.
Across the year
Southwest on LAS to BWI through the year
Delays peak in May, when the on-time rate falls to 67.6%. January is the strongest month at 91.0%. Moving a flexible trip across that boundary buys 23 points. July was the busiest month here, with 149 flights.
Across the week, Saturday is the strongest day at 88.1% on time and Sunday the weakest at 69.6%, a spread of 19 points.
Arrival by arrival
How late Southwest on LAS to BWI runs when it is late
The 342 late arrivals split 155 under half an hour, 109 between 30 and 60 minutes, and 78 an hour or more.
- 15+ min early390 flights24.4%
- Within 15 min867 flights54.2%
- 15–29 min late155 flights9.7%
- 30–59 min late109 flights6.8%
- 1–2 hours late62 flights3.9%
- 2+ hours late16 flights1.0%
Scale runs 0% to 100%.
Share of 1,599 completed flights by arrival against schedule.
A late pushback is often recovered here: of 500 departures that left 15 minutes late or more, 195 still arrived on time. 37 flights left on time and still arrived late.
The worst days
Worst days for Southwest on LAS to BWI
The latest arrival of the period was on 18 May 2026, 5 hours 44 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The same cause led on five of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 18 May 2026 | 5 hours 44 minutes | Late-arriving aircraft |
| 6 March 2026 | 4 hours 19 minutes | Late-arriving aircraft |
| 18 May 2026 | 3 hours 25 minutes | Late-arriving aircraft |
| 17 April 2026 | 3 hours 1 minute | Late-arriving aircraft |
| 17 April 2026 | 2 hours 43 minutes | Late-arriving aircraft |
Delay causes
Why Southwest runs late on this route
Carrier accounts for 49% of the 15,000 delay minutes carriers reported here, and the remaining four split what is left.
- 49%Carrier
- 39%Late-arriving aircraft
- 11%National Airspace System
- 0%Security
- 0%Extreme weather
39% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 15,000 reported delay minutes here, that single category outweighs weather by 39 to one. The split is drawn from 15,369 reported delay minutes.
The largest share of delay minutes, 49%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 7,509 of the 15,000 delay minutes reported here.
Cancellations sit at 1.10% against a national 1.89%, which is ordinary. Diversions add another 0.80%.
Connections and stage length
What a delay here costs
Badly late arrivals are rare here: only 4.9% land an hour or more behind schedule, against 8.3% 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 2,106 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
The return leg runs 78.3% on time across 1,624 flights, within half a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 1,630 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 LAS to BWI
Put together: the calendar is the biggest lever here, not the carrier or the hour. January runs 91.0% on time and May 67.6%, a swing of 23 points. If the dates move at all, move them out of May before you think about anything else. 1,599 completed flights over 12 months sit behind that.
Related
Where to go next
- LAS to BWI, every carrier
- Southwest on BWI to LAS, the return leg
- Spirit Airlines on LAS to BWI82.3%
- Southwest Airlines network-wide record
- Harry Reid International (LAS) delay statistics
- Baltimore/Washington International Thurgood Marshall (BWI) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.