Carrier route record

WNBZN→DEN

Southwest Airlines · Bozeman to Denver

Flights: 1,174
Period: July 2025 to June 2026
Share of route: 43%
Carriers: 3

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

Southwest on BZN to DEN sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 1,174 flights. The strongest carrier on the route with a full sample, United Airlines, flew 1,163 at 78.8% on time.

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

On time

74.6%

Arrivals under 15 minutes late, of 1,166 completed flights

Avg delay

57 min

Across delayed arrivals only, not all flights

Cancelled

0.26%

National rate is 1.81%

Whole route

76.9%

Every carrier on BZN to DEN, 2,730 flights

These figures cover 1,174 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 BZN to DEN

Southwest flew 1,174 of the 2,730 flights on BZN to DEN, about 43% of it. Its 74.6% on time is 2 points worse than the route as a whole, which runs 76.9%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from United at 78.8% to Southwest at 74.6%.

The two carriers here are closely matched: about a point separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.

On-time performance by carrier on BZN to DEN
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	1,163	78.8%	73 min	0.43%	B+
SkyWest Airlines	393	77.8%	71 min	1.27%	B
Southwest Airlines (this page)	1,174	74.6%	57 min	0.26%	C+

No carrier stands out. United tops the table at 78.8%, about a point clear of the bottom, which is inside the range this kind of sample moves year to year.

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 31 points, against about a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am333 flights90.7%
8am–11am202 flights71.6%
11am–2pm196 flights81.5%
2pm–5pm298 flights59.5%
5pm–8pm145 flights62.9%
8pm–5am—

Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 90.7% of the time, against 59.5% for the afternoon window. That is 31 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 333 flights scheduled in it.

Across the year

Southwest on BZN to DEN through the year

Darker means more delays. Figures are on-time percentages.October best, June worst

June is the worst month at 59.8% on time, 27 points below October, the best at 86.6%. 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. July was the busiest month here, with 120 flights.

Across the week, Monday is the strongest day at 81.2% on time and Friday the weakest at 67.9%. 13 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 17,000 reported delay minutes.

National Airspace System
41%
Late-arriving aircraft
37%
Carrier
21%
Extreme weather
1%

37% 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 17,000 reported delay minutes here, that single category outweighs weather by 37 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 16,743 reported delay minutes.

41% 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 6,895 minutes out of 17,000, against a national NAS share of 21%.

Cancellations are rare at 0.26%, 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 524 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 70.5% on time across 1,173 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 1,174 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 BZN to DEN

Put together: the calendar is the biggest lever here, not the carrier or the hour. October runs 86.6% on time and June 59.8%, a swing of 27 points. If the dates move at all, move them out of June before you think about anything else. 1,166 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