Carrier route record
DLJFK→DEN
Delta Air Lines · New York to Denver
- Flights
- 978
- Period
- July 2025 to June 2026
- Share of route
- 62%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.
Delta on JFK 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, 4 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 978 flights, with a median arrival 5 minutes early.
The national on-time rate over the same period is 77.6%, so Delta on JFK to DEN runs 4 points behind the country as a whole. Across a thousand flights that is about 44 extra late arrivals.
Key figures
On time
73.2%
Arrivals under 15 minutes late, of 950 completed flights
Avg delay
71 min
Across delayed arrivals only, not all flights
Cancelled
2.56%
National rate is 1.81%
Whole route
71.4%
Every carrier on JFK to DEN, 1,572 flights
These figures cover 978 flights between July 2025 and June 2026. Beyond the headline rate, 10.6% 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 JFK to DEN
Delta flew 978 of the 1,572 flights on JFK to DEN, most of the route. Its 73.2% on time is 2 points better than the route as a whole, which runs 71.4%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from Delta at 73.2% to Frontier at 67.3%. 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 |
|---|---|---|---|---|---|
| Delta Air Lines (this page) | 978 | 73.2% | 71 min | 2.56% | C |
| JetBlue Airways | 545 | 68.7% | 55 min | 2.75% | C |
| Frontier Airlinesthin sample | 49 | 67.3% | 124 min | 0.00% | C+ |
Flight by flight
Delta flight numbers on JFK to DEN
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 21 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–8am1 flights—
- 8am–11am362 flights83.0%
- 11am–2pm—
- 2pm–5pm201 flights62.0%
- 5pm–8pm157 flights63.6%
- 8pm–5am257 flights73.6%
Scale runs 55% to 90%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 83.0% of the time, against 62.0% for the afternoon window. That is 21 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 362 flights scheduled in it.
Across the year
Delta on JFK to DEN through the year
July is the worst month at 53.6% on time, 37 points below February, the best at 90.4%. 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 92 flights.
Across the week, Tuesday is the strongest day at 83.0% on time and Thursday the weakest at 67.9%. 15 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Delta 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 18,000 reported delay minutes.
- 39%Carrier
- 34%National Airspace System
- 25%Late-arriving aircraft
- 2%Extreme weather
The largest share of delay minutes, 39%, 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 7,013 of the 18,000 delay minutes reported here. The split is drawn from 18,202 reported delay minutes.
34% 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 6,203 minutes out of 18,000, against a national NAS share of 21%.
Cancellations run at 2.56%, against 1.81% nationally. That is about one flight in 40 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.6% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
At 1,626 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.
The return leg is a different operation and performs like one: it runs 87.0% on time across 978 flights, 14 points above 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 14 points of difference.
One caution: this is a thin sample. 978 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 JFK to DEN
Put together: treat all of this as provisional. 978 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 73.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 950 completed flights over 12 months sit behind that.
Related
Where to go next
- JFK to DEN, every carrier
- Delta on DEN to JFK, the return leg
- JetBlue Airways on JFK to DEN68.7%
- Delta Air Lines network-wide record
- John F. Kennedy International (JFK) delay statistics
- Denver International (DEN) delay statistics
- The US routes with the most cancellations
- 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.