Carrier route record

DLDEN→LAX

Delta Air Lines · Denver to Los Angeles

Flights: 746
Period: July 2025 to June 2026
Share of route: 10%
Carriers: 5

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

Delta on DEN to LAX lands a B, 3 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That is a workable record, not a spotless one. That rests on 746 flights. The strongest carrier on the route with a full sample, United Airlines, flew 3,064 at 84.5% on time.

United Airlines is the most reliable of the four carriers covered here at 84.5% on time across 3,064 flights.

On time

80.5%

Arrivals under 15 minutes late, of 735 completed flights

Avg delay

89 min

Across delayed arrivals only, not all flights

Cancelled

1.47%

National rate is 1.81%

Whole route

79.0%

Every carrier on DEN to LAX, 7,721 flights

These figures cover 746 flights between July 2025 and June 2026. The median arrival is 9 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

Delta against every carrier on DEN to LAX

Delta flew 746 of the 7,721 flights on DEN to LAX, about 10% of it. Its 80.5% on time is 2 points better than the route as a whole, which runs 79.0%. Ranked by on-time rate it is number three of five carriers on the route, where the range runs from United at 84.5% to Southwest at 68.0%.

The choice of carrier is not cosmetic here. United Airlines arrives on time 84.5% of the time; Southwest Airlines manages 68.0%. Sample sizes sit next to every figure, because a two-point gap across 1,918 flights means less than a ten-point one.

On-time performance by carrier on DEN to LAX
Airline	Flights	On time	Avg delay	Cancelled	Grade
United Airlines	3,064	84.5%	58 min	0.00%	B+
Frontier Airlines	762	81.1%	75 min	0.52%	B+
Delta Air Lines (this page)	746	80.5%	89 min	1.47%	B
SkyWest Airlines	1,231	80.1%	82 min	0.81%	B+
Southwest Airlines	1,918	68.0%	49 min	0.73%	C+

The spread between United and Southwest is 17 points, wide enough that it should decide the booking. On a hundred trips that is 17 more arrivals inside the on-time window.

Flight by flight

Delta flight numbers on DEN to LAX

DL 200206:1588.3% · 267 flights

Departure window

When Delta runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 24 points, against 17 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am267 flights88.3%
8am–11am—
11am–2pm243 flights87.1%
2pm–5pm—
5pm–8pm212 flights64.3%
8pm–5am24 flights—

Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 64.3% on time, against 88.3% 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 5am–8am window is the busiest, with 267 flights scheduled in it.

Across the year

Delta on DEN to LAX through the year

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

July is the worst month at 71.9% on time, 18 points below September, the best at 90.0%. 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. August was the busiest month here, with 93 flights.

Across the week, Monday is the strongest day at 83.5% on time and Sunday the weakest at 75.5%. 8 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Delta runs late on this route

One category carries most of the weight here. Late-arriving aircraft accounts for 48% of the 13,000 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
48%
Carrier
43%
National Airspace System
7%
Extreme weather
1%

48% 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 13,000 reported delay minutes here, that single category outweighs weather by 36 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 12,698 reported delay minutes.

The largest share of delay minutes, 43%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 5,494 of the 13,000 delay minutes reported here.

Cancellations sit at 1.47% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

7.9% 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 an hour and a half, which a normal layover absorbs.

The 862 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 runs 79.7% on time across 744 flights, within about a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 746 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 Delta on DEN to LAX

Put together: treat all of this as provisional. 746 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 80.5% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 735 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