Carrier route record
DLLAX→DEN
Delta Air Lines · Los Angeles to Denver
- Flights
- 744
- 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 LAX to DEN lands a B, 2 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 744 flights. The strongest carrier on the route with a full sample, United Airlines, flew 3,067 at 87.1% on time.
United Airlines is the most reliable of the four carriers covered here at 87.1% on time across 3,067 flights.
Key figures
On time
79.7%
Arrivals under 15 minutes late, of 729 completed flights
Avg delay
85 min
Across delayed arrivals only, not all flights
Cancelled
1.48%
National rate is 1.81%
Whole route
81.7%
Every carrier on LAX to DEN, 7,721 flights
These figures cover 744 flights between July 2025 and June 2026. Beyond the headline rate, 8.8% 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
Delta against every carrier on LAX to DEN
Delta flew 744 of the 7,721 flights on LAX to DEN, about 10% of it. Its 79.7% on time is 2 points worse than the route as a whole, which runs 81.7%. Ranked by on-time rate it is number four of five carriers on the route, where the range runs from United at 87.1% to Southwest at 74.1%.
The choice of carrier is not cosmetic here. United Airlines arrives on time 87.1% of the time; Southwest Airlines manages 74.1%. Sample sizes sit next to every figure, because a two-point gap across 1,917 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 3,067 | 87.1% | 68 min | 0.10% | A+ |
| Frontier Airlines | 762 | 81.9% | 90 min | 0.79% | B+ |
| SkyWest Airlines | 1,231 | 81.2% | 61 min | 0.81% | B+ |
| Delta Air Lines (this page) | 744 | 79.7% | 85 min | 1.48% | B |
| Southwest Airlines | 1,917 | 74.1% | 52 min | 0.47% | C+ |
The spread between United and Southwest is 13 points, wide enough that it should decide the booking. On a hundred trips that is 13 more arrivals inside the on-time window.
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 20 points, against 13 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am243 flights87.1%
- 11am–2pm12 flights—
- 2pm–5pm227 flights67.6%
- 5pm–8pm18 flights—
- 8pm–5am244 flights82.4%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 87.1% of the time, against 67.6% for the afternoon window. That is 20 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8pm–5am window is the busiest, with 244 flights scheduled in it.
Across the year
Delta on LAX to DEN through the year
July is the worst month at 60.9% on time, 28 points below October, the best at 89.0%. 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, Wednesday is the strongest day at 82.7% on time and Saturday the weakest at 76.6%. 6 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. Carrier accounts for 60% 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.
- 60%Carrier
- 26%National Airspace System
- 13%Late-arriving aircraft
- 1%Extreme weather
- 0%Security
The largest share of delay minutes, 60%, 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 7,541 of the 13,000 delay minutes reported here. The split is drawn from 12,566 reported delay minutes.
Cancellations sit at 1.48% against a national 1.81%, which is ordinary. Diversions add another 0.54%.
Connections and stage length
What a delay here costs
8.8% 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 80.5% on time across 746 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. 744 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 LAX to DEN
Put together: treat all of this as provisional. 744 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 79.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 729 completed flights over 12 months sit behind that.
Related
Where to go next
- LAX to DEN, every carrier
- Delta on DEN to LAX, the return leg
- United Airlines on LAX to DEN87.1%
- Frontier Airlines on LAX to DEN81.9%
- SkyWest Airlines on LAX to DEN81.2%
- Southwest Airlines on LAX to DEN74.1%
- Delta Air Lines network-wide record
- Los Angeles International (LAX) delay statistics
- Denver International (DEN) delay statistics
- Same route, different airline: where the carrier you pick matters most
- The best time of day to fly, according to 7.04 million flight records
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.