Carrier route record
WNDEN→LGA
Southwest Airlines · Denver to New York
- Flights
- 1,517
- Period
- September 2025 to August 2026
- Share of route
- 33%
- Carriers
- 4
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on DEN to LGA draws a D−. Roughly one flight in three arrives at least 15 minutes late, and the typical late arrival is about an hour behind schedule. Build slack into anything you connect to. That rests on 1,517 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 1,033 at 79.7% on time.
The national on-time rate over the same period is 77.3%, so Southwest on DEN to LGA runs 14 points behind the country as a whole. Across a thousand flights that is about 143 extra late arrivals.
Key figures
On time
63.0%
Arrivals under 15 minutes late, of 1,447 completed flights
Avg delay
59 min
Across delayed arrivals only, not all flights
Cancelled
3.10%
National rate is 1.89%
Whole route
71.3%
Every carrier on DEN to LGA, 4,664 flights
These figures cover 1,517 flights between September 2025 and August 2026. Beyond the headline rate, 12.6% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Southwest against every carrier on DEN to LGA
Southwest flew 1,517 of the 4,664 flights on DEN to LGA, about 33% of it. Its 63.0% on time is 8 points worse than the route as a whole, which runs 71.3%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from Delta at 79.7% to Southwest at 63.0%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 79.7% of the time; United Airlines manages 73.5%. Sample sizes sit next to every figure, because a two-point gap across 2,021 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 1,033 | 79.7% | 83 min | 4.84% | B− |
| United Airlines | 2,021 | 73.5% | 74 min | 1.78% | C |
| Frontier Airlinesthin sample | 93 | 65.6% | 93 min | 3.23% | C− |
| Southwest Airlines (this page) | 1,517 | 63.0% | 59 min | 3.10% | D− |
Delta Air Lines cancels 4.8% 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.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
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 6 points between the best and worst carrier.
- 5am–8am282 flights91.3%
- 8am–11am392 flights69.6%
- 11am–2pm239 flights57.9%
- 2pm–5pm266 flights43.8%
- 5pm–8pm338 flights49.1%
- 8pm–5am—
Scale runs 35% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 91.3% of the time, against 43.8% for the afternoon window. That is 48 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 392 flights scheduled in it.
Across the year
Southwest on DEN to LGA through the year
June is the worst month at 49.6% on time, 30 points below February, the best at 79.4%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. July was the busiest month here, with 147 flights.
Across the week, Wednesday is the strongest day at 69.0% on time and Sunday the weakest at 53.4%, a spread of 16 points.
Arrival by arrival
How late Southwest on DEN to LGA runs when it is late
The 536 late arrivals split 175 under half an hour, 178 between 30 and 60 minutes, and 183 an hour or more.
- 15+ min early208 flights14.4%
- Within 15 min703 flights48.6%
- 15–29 min late175 flights12.1%
- 30–59 min late178 flights12.3%
- 1–2 hours late120 flights8.3%
- 2+ hours late63 flights4.4%
Scale runs 0% to 100%.
Share of 1,447 completed flights by arrival against schedule.
112 of 566 late departures made up the time and arrived on time, 20% of them. In the other direction, 82 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at LGA.
The worst days
Worst days for Southwest on DEN to LGA
The latest arrival of the period was on 14 December 2025, 5 hours 26 minutes behind schedule; most of its delay minutes were filed as national airspace system delay. The same cause led on four of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 14 December 2025 | 5 hours 26 minutes | National Airspace System |
| 1 April 2026 | 5 hours 17 minutes | National Airspace System |
| 29 March 2026 | 4 hours 44 minutes | National Airspace System |
| 9 November 2025 | 4 hours | National Airspace System |
| 12 March 2026 | 3 hours 50 minutes | Late-arriving aircraft |
Delay causes
Why Southwest runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 32,000 reported delay minutes.
- 40%National Airspace System
- 33%Carrier
- 26%Late-arriving aircraft
- 1%Extreme weather
- 0%Security
40% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 13,000 minutes out of 32,000, against a national NAS share of 21%. The split is drawn from 31,843 reported delay minutes.
Cancellations run at 3.10%, against 1.89% 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
12.6% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection 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 is a different operation and performs like one: it runs 59.3% on time across 1,516 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 1,517 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 DEN to LGA
Put together: the delay figures matter less here than the 3.10% 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. 1,447 completed flights over 12 months sit behind that.
Related
Where to go next
- DEN to LGA, every carrier
- Southwest on LGA to DEN, the return leg
- Delta Air Lines on DEN to LGA79.7%
- United Airlines on DEN to LGA73.5%
- Southwest Airlines network-wide record
- Denver International (DEN) delay statistics
- LaGuardia (LGA) delay statistics
- The US routes with the most cancellations
- What a cancellation rate actually tells you (and what it hides)
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.