Carrier route record

DLJFK→SAN

Delta Air Lines · New York to San Diego

Flights: 1,036
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 Delta Air Lines.

Delta on JFK to SAN lands a B, about a point worse than the national rate of 77.6%. About 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 1,036 flights. The strongest carrier on the route with a full sample, JetBlue Airways, flew 727 at 85.7% on time.

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

On time

76.6%

Arrivals under 15 minutes late, of 994 completed flights

Avg delay

57 min

Across delayed arrivals only, not all flights

Cancelled

2.80%

National rate is 1.81%

Whole route

79.1%

Every carrier on JFK to SAN, 2,413 flights

These figures cover 1,036 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 JFK to SAN

Delta flew 1,036 of the 2,413 flights on JFK to SAN, about 43% of it. Its 76.6% on time is 3 points worse than the route as a whole, which runs 79.1%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from JetBlue at 85.7% to Alaska at 75.7%.

The choice of carrier is not cosmetic here. JetBlue Airways arrives on time 85.7% of the time; Alaska Airlines manages 75.7%. Sample sizes sit next to every figure, because a two-point gap across 650 flights means less than a ten-point one.

On-time performance by carrier on JFK to SAN
Airline	Flights	On time	Avg delay	Cancelled	Grade
JetBlue Airways	727	85.7%	61 min	2.48%	A
Delta Air Lines (this page)	1,036	76.6%	57 min	2.80%	B
Alaska Airlines	650	75.7%	56 min	1.69%	B

JetBlue leads Alaska by 10 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

Flight by flight

Delta flight numbers on JFK to SAN

DL 68520:2574.9% · 307 flights

Departure window

When Delta runs best on this route

Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 1,036 flights.

5am–8am—
8am–11am365 flights80.7%
11am–2pm—
2pm–5pm15 flights—
5pm–8pm352 flights73.4%
8pm–5am304 flights74.7%

Scale runs 65% to 85%. Rows with fewer than 30 flights show a dash.

The early departures do better, though not dramatically: 80.7% on time for the 8am–11am window against 73.4% for 5pm–8pm. Worth taking if the schedule allows, not worth an extra connection. The 8am–11am window is the busiest, with 365 flights scheduled in it.

Across the year

Delta on JFK to SAN through the year

Darker means more delays. Figures are on-time percentages.August best, January worst

January is the weak month at 64.4% on time, against 84.9% in August. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. May was the busiest month here, with 93 flights.

Across the week, Monday is the strongest day at 81.4% on time and Sunday the weakest at 67.6%. 14 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 42% 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.

Carrier
42%
National Airspace System
38%
Late-arriving aircraft
16%
Extreme weather
3%
Security
1%

38% 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 5,090 minutes out of 13,000, against a national NAS share of 21%. The split is drawn from 13,343 reported delay minutes.

The largest share of delay minutes, 42%, 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 5,645 of the 13,000 delay minutes reported here.

Cancellations run at 2.80%, against 1.81% nationally. That is roughly 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

6.8% 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 about an hour, which a normal layover absorbs.

At 2,446 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 83.5% on time across 1,036 flights, 7 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 7 points of difference.

One caution: this is a thin sample. 1,036 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 SAN

Put together: the delay figures matter less here than the 2.80% cancellation rate. A late arrival costs you about an hour; a cancelled flight costs you the day. Book the 8am–11am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 994 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