Carrier route record
WNLGA→DEN
Southwest Airlines · New York to Denver
- Flights
- 1,467
- Period
- July 2025 to June 2026
- Share of route
- 31%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on LGA to DEN carries a cancellation problem, not just a delay problem: 3.3% of scheduled flights never operate, against 1.8% nationally. Of the ones that do fly, a little over half of flights arrive on time, worth a D− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 1,467 flights. The strongest carrier on the route with a full sample, United Airlines, flew 2,017 at 77.8% on time.
The national on-time rate over the same period is 77.6%, so Southwest on LGA to DEN runs 16 points behind the country as a whole. Across a thousand flights that is about 165 extra late arrivals.
Key figures
On time
61.1%
Arrivals under 15 minutes late, of 1,414 completed flights
Avg delay
63 min
Across delayed arrivals only, not all flights
Cancelled
3.27%
National rate is 1.81%
Whole route
70.7%
Every carrier on LGA to DEN, 4,672 flights
These figures cover 1,467 flights between July 2025 and June 2026. Beyond the headline rate, 13.2% 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 LGA to DEN
Southwest flew 1,467 of the 4,672 flights on LGA to DEN, about 31% of it. Its 61.1% on time is 10 points worse than the route as a whole, which runs 70.7%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from United at 77.8% to Southwest at 61.1%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. United Airlines arrives on time 77.8% of the time; Delta Air Lines manages 71.3%. Sample sizes sit next to every figure, because a two-point gap across 1,036 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 2,017 | 77.8% | 71 min | 1.98% | B |
| Delta Air Lines | 1,036 | 71.3% | 71 min | 4.15% | C− |
| Frontier Airlinesthin sample | 152 | 64.4% | 105 min | 3.95% | D− |
| Southwest Airlines (this page) | 1,467 | 61.1% | 63 min | 3.27% | D− |
Delta Air Lines cancels 4.2% 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 46 points, against 7 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am345 flights85.3%
- 8am–11am158 flights64.3%
- 11am–2pm196 flights67.4%
- 2pm–5pm362 flights52.0%
- 5pm–8pm214 flights39.1%
- 8pm–5am192 flights48.6%
Scale runs 30% to 90%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 39.1% on time, against 85.3% 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 2pm–5pm window is the busiest, with 362 flights scheduled in it.
Across the year
Southwest on LGA to DEN through the year
Delays peak in March, when the on-time rate falls to 48.1%. January is the strongest month at 77.5%. Moving a flexible trip across that boundary buys 29 points. June was the busiest month here, with 142 flights.
Across the week, Saturday is the strongest day at 72.6% on time and Monday the weakest at 53.1%. 19 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 50% of the 35,000 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.
- 50%Late-arriving aircraft
- 25%National Airspace System
- 23%Carrier
- 1%Extreme weather
- 0%Security
50% 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 35,000 reported delay minutes here, that single category outweighs weather by 40 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 34,883 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 85.3% on time here.
Cancellations run at 3.27%, against 1.81% nationally. That is about one flight in 30 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 13.2% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 1,620 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 64.0% on time across 1,467 flights, within 3 points 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 1,467 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 LGA to DEN
Put together: the delay figures matter less here than the 3.27% cancellation rate. A late arrival costs you about an hour; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 1,414 completed flights over 12 months sit behind that.
Related
Where to go next
- LGA to DEN, every carrier
- Southwest on DEN to LGA, the return leg
- United Airlines on LGA to DEN77.8%
- Delta Air Lines on LGA to DEN71.3%
- Frontier Airlines on LGA to DEN64.4%
- Southwest Airlines network-wide record
- LaGuardia (LGA) delay statistics
- Denver International (DEN) delay statistics
- The US routes with the most cancellations
- 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.