Carrier route record
WNEUG→DEN
Southwest Airlines · Eugene to Denver
- Flights
- 427
- Period
- July 2025 to June 2026
- Share of route
- 34%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.
Southwest on EUG to DEN sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 5 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 427 flights, with a median arrival right on schedule.
The national on-time rate over the same period is 77.6%, so Southwest on EUG to DEN runs 5 points behind the country as a whole. Across a thousand flights that is about 48 extra late arrivals.
Key figures
On time
72.8%
Arrivals under 15 minutes late, of 423 completed flights
Avg delay
61 min
Across delayed arrivals only, not all flights
Cancelled
0.23%
National rate is 1.81%
Whole route
79.2%
Every carrier on EUG to DEN, 1,271 flights
These figures cover 427 flights between July 2025 and June 2026. Beyond the headline rate, 8.3% 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 EUG to DEN
Southwest flew 427 of the 1,271 flights on EUG to DEN, about 34% of it. Its 72.8% on time is 6 points worse than the route as a whole, which runs 79.2%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from United at 84.9% to SkyWest at 67.5%. 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 |
|---|---|---|---|---|---|
| United Airlines | 728 | 84.9% | 99 min | 0.41% | B+ |
| Southwest Airlines (this page) | 427 | 72.8% | 61 min | 0.23% | C+ |
| SkyWest Airlinesthin sample | 116 | 67.5% | 59 min | 1.72% | C |
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 42 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–8am131 flights91.5%
- 8am–11am—
- 11am–2pm165 flights76.2%
- 2pm–5pm131 flights49.6%
- 5pm–8pm—
- 8pm–5am—
Scale runs 40% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 91.5% of the time, against 49.6% for the afternoon window. That is 42 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 11am–2pm window is the busiest, with 165 flights scheduled in it.
Across the year
Southwest on EUG to DEN through the year
- Jul–Sep 202589 flights67.0%
- Oct–Dec 202587 flights70.9%
- Jan–Mar 202679 flights88.5%
- Apr–Jun 2026172 flights69.6%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 72.8% on time across 427 flights.
Southwest on EUG to DEN did not run the same all year. Its best quarter was Jan–Mar 2026 at 88.5% on time and its weakest Jul–Sep 2025 at 67.0%, a swing of 22 points on roughly 107 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
Across the week, Wednesday is the strongest day at 82.8% on time and Friday the weakest at 60.6%. 22 points is a smaller lever than departure hour, but it is free.
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 6,990 reported delay minutes.
- 36%National Airspace System
- 30%Carrier
- 27%Late-arriving aircraft
- 8%Extreme weather
- 0%Security
36% 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 2,487 minutes out of 6,990, against a national NAS share of 21%. The split is drawn from 6,990 reported delay minutes.
Cancellations are rare at 0.23%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
8.3% 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 996 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 69.8% on time across 428 flights, 3 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 3 points of difference.
One caution: this is a thin sample. 427 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.
What to do with this
Booking Southwest on EUG to DEN
Put together: treat all of this as provisional. 427 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 72.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 423 completed flights over 12 months sit behind that.
Related
Where to go next
- EUG to DEN, every carrier
- Southwest on DEN to EUG, the return leg
- United Airlines on EUG to DEN84.9%
- SkyWest Airlines on EUG to DEN67.5%
- Southwest Airlines network-wide record
- Denver International (DEN) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Connecting flights: how much buffer the data says you need
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.