Carrier route record
DLJFK→SFO
Delta Air Lines · New York to San Francisco
- Flights
- 2,229
- Period
- July 2025 to June 2026
- Share of route
- 33%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.
Delta on JFK to SFO sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 6 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 2,229 flights. The strongest carrier on the route with a full sample, American Airlines, flew 1,448 at 77.2% on time.
American Airlines is the most reliable of the three carriers covered here at 77.2% on time across 1,448 flights.
Key figures
On time
71.3%
Arrivals under 15 minutes late, of 2,192 completed flights
Avg delay
70 min
Across delayed arrivals only, not all flights
Cancelled
1.48%
National rate is 1.81%
Whole route
74.1%
Every carrier on JFK to SFO, 6,730 flights
These figures cover 2,229 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 SFO
Delta flew 2,229 of the 6,730 flights on JFK to SFO, about 33% of it. Its 71.3% on time is 3 points worse than the route as a whole, which runs 74.1%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from American at 77.2% to Delta at 71.3%.
The three carriers here are closely matched: 6 points 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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| American Airlines | 1,448 | 77.2% | 66 min | 2.56% | B |
| JetBlue Airways | 1,945 | 76.7% | 75 min | 2.01% | B |
| Alaska Airlines | 1,108 | 71.4% | 70 min | 1.81% | C |
| Delta Air Lines (this page) | 2,229 | 71.3% | 70 min | 1.48% | C |
No carrier stands out. American tops the table at 77.2%, 6 points clear of the bottom, which is inside the range this kind of sample moves year to year.
Flight by flight
Delta flight numbers on JFK to SFO
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 19 points, against 6 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am358 flights74.0%
- 8am–11am366 flights77.8%
- 11am–2pm350 flights76.6%
- 2pm–5pm403 flights74.2%
- 5pm–8pm520 flights59.3%
- 8pm–5am232 flights70.0%
Scale runs 50% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 59.3% on time, against 77.8% for the 8am–11am 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 5pm–8pm window is the busiest, with 520 flights scheduled in it.
Across the year
Delta on JFK to SFO through the year
December is the weak month at 52.5% on time, against 91.4% 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. October was the busiest month here, with 201 flights.
Across the week, Tuesday is the strongest day at 80.3% on time and Sunday the weakest at 67.1%. 13 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. National Airspace System accounts for 49% of the 44,000 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.
- 49%National Airspace System
- 38%Carrier
- 11%Late-arriving aircraft
- 2%Extreme weather
- 0%Security
The largest share of delay minutes, 38%, 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 17,000 of the 44,000 delay minutes reported here. The split is drawn from 44,036 reported delay minutes.
49% 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 21,000 minutes out of 44,000, against a national NAS share of 21%.
Cancellations sit at 1.48% against a national 1.81%, which is ordinary. Diversions add another 0.18%.
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 2,586 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 79.9% on time across 2,229 flights, 9 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 9 points of difference.
The sample behind these figures is 2,229 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 Delta on JFK to SFO
Put together: the calendar is the biggest lever here, not the carrier or the hour. August runs 91.4% on time and December 52.5%, a swing of 39 points. If the dates move at all, move them out of December before you think about anything else. 2,192 completed flights over 12 months sit behind that.
Related
Where to go next
- JFK to SFO, every carrier
- Delta on SFO to JFK, the return leg
- American Airlines on JFK to SFO77.2%
- JetBlue Airways on JFK to SFO76.7%
- Alaska Airlines on JFK to SFO71.4%
- Delta Air Lines network-wide record
- John F. Kennedy International (JFK) delay statistics
- San Francisco International (SFO) delay statistics
- How often a connection fails at the major US hubs
- 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.