Carrier route record

WNSNA→DEN

Southwest Airlines · Santa Ana to Denver

Flights: 1,535
Period: July 2025 to June 2026
Share of route: 42%
Carriers: 3

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Southwest Airlines.

Southwest on SNA to DEN lands a B+, level with the national rate of 77.6%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 1,535 flights, with a median arrival 3 minutes early.

The US average over the same twelve months is 77.6%, so there is little to separate Southwest on SNA to DEN from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

77.5%

Arrivals under 15 minutes late, of 1,522 completed flights

Avg delay

57 min

Across delayed arrivals only, not all flights

Cancelled

0.46%

National rate is 1.81%

Whole route

82.4%

Every carrier on SNA to DEN, 3,697 flights

These figures cover 1,535 flights between July 2025 and June 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.

Carrier by carrier

Southwest against every carrier on SNA to DEN

Southwest flew 1,535 of the 3,697 flights on SNA to DEN, about 42% of it. Its 77.5% on time is 5 points worse than the route as a whole, which runs 82.4%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from United at 86.1% to Southwest at 77.5%. 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.

On-time performance by carrier on SNA to DEN
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	1,870	86.1%	64 min	0.37%	A+
Frontier Airlinesthin sample	292	84.9%	91 min	0.34%	B+
Southwest Airlines (this page)	1,535	77.5%	57 min	0.46%	B+

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 32 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–8am314 flights92.6%
8am–11am297 flights90.2%
11am–2pm242 flights83.8%
2pm–5pm374 flights62.1%
5pm–8pm208 flights60.7%
8pm–5am100 flights69.0%

Scale runs 50% to 100%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 60.7% on time, against 92.6% 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 374 flights scheduled in it.

Across the year

Southwest on SNA to DEN through the year

Darker means more delays. Figures are on-time percentages.April best, July worst

July is the worst month at 61.9% on time, 27 points below April, the best at 88.6%. 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. May was the busiest month here, with 136 flights.

Across the week, Saturday is the strongest day at 85.7% on time and Sunday the weakest at 71.9%. 14 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 44% of the 19,000 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.

Late-arriving aircraft
44%
National Airspace System
33%
Carrier
18%
Extreme weather
4%
Security
0%

44% 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 19,000 reported delay minutes here, that single category outweighs weather by 10 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 19,465 reported delay minutes.

33% 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 6,470 minutes out of 19,000, against a national NAS share of 21%.

Cancellations are rare at 0.46%, 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

7.0% 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 846 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 73.1% on time across 1,534 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 1,535 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 SNA to DEN

Put together: the calendar is the biggest lever here, not the carrier or the hour. April runs 88.6% on time and July 61.9%, a swing of 27 points. If the dates move at all, move them out of July before you think about anything else. 1,522 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures