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Rankings / Routes / New York to San Francisco

2025 flights

New York to San Francisco

Between New York and San Francisco, 3.6 million passengers flew nonstop in 2025, on 22 thousand flights of about 2,578 miles and 5.3 hours in the air. The average passenger accounted for about 414 kg of CO2 from the fuel burned, from 296 kg on Alaska Airlines to 659 kg on American Airlines.

  • 414 kgCO2 per passenger, average
  • 2,578 milesabout 5.3 hours in the air
  • 3.6 millionpassengers in 2025
  • 88%of seats filled

CO2 per passenger, airline by airline

CO2 per passenger by airline, New York to San FranciscoBar chart of kilograms of CO2 per passenger on each airline between New York and San Francisco in 2025.0200400600Alaska Airlines296 kgJetBlue350 kgUnited Airlines414 kgDelta Air Lines462 kgAmerican Airlines659 kg
CO2 per passenger by airline, New York to San FranciscoBar chart of kilograms of CO2 per passenger on each airline between New York and San Francisco in 2025.0200400600Alaska Airlines296 kgJetBlue350 kgUnited Airlines414 kgDelta Air Lines462 kgAmerican Airlines659 kg
Kilograms of CO2 per passenger, one way, 2025. Fuel burned only. Less is better.
New York to San Francisco by airline, 2025
AirlineShare of passengersFlights (thousands)Main aircraftSeats per flightSeats filledkg CO2 per passenger
United Airlines42%7.3Boeing 757-200, Boeing 777-20023789%414
Delta Air Lines21%4.4Boeing 767-300ER, Boeing 757-20019988%462
Alaska Airlines16%3.7Boeing 737 MAX 9, Boeing 737-900ER17688%296
JetBlue14%3.8Airbus A321, Airbus A321neo15986%350
American Airlines7%2.8Airbus A32110288%659

What explains the differences

It's number 17 of the 100 busiest city pairs by passengers, and number 59 for the lowest CO2 per mile flown (0.16 kg per passenger-mile, number 1 being the lowest). A typical route of 2,578 miles in this set comes out at about 345 kg, so this one is 20% above it.

The flights use more than one pair of airports: JFK to SFO (52%), EWR to SFO (48%), JFK to SJC (0%). The figures here cover all of them.

The airlines on this route differ by 122% per passenger. Alaska Airlines burned 4,677 gallons per flight and 154 passengers on each, and American Airlines 6,052 gallons and 90 passengers. Fuel burned per flight explains about 32% of the gap and the number of passengers on each flight the other 68%. Alaska Airlines flew 88% full here against 88% for American Airlines, flying mostly Boeing 737 MAX 9 against Airbus A321.

For comparison, the EPA default factor for a flight of this length (0.163 kg per passenger-mile) would give 420 kg. The EPA figure is a national average for flights of that length. The measured figure for this route is 1.5% lower.

2019 compared with 2025

In 2019 the route carried 4.5 million passengers on 30 thousand flights. In 2025 it carried 3.6 million, down 19%, on 22 thousand flights, down 27%. The average flight had 172 seats then and 188 now, and 87% of them were filled against 88%.

CO2 per passenger was 412 kg in 2019 and 414 kg in 2025, up 0.5%. Fuel burned per flight was up 10.8% (6,347 gallons to 7,033) and passengers per flight were up 10.2% (150 to 166). The distance flown was about the same (2,576 miles then, 2,578 now).

United Airlines led in both years, with 39% of passengers in 2019 and 42% in 2025. Alaska Airlines lost the most, 20% to 16%.

Airline by airline, Alaska Airlines went from 333 kg to 296 kg per passenger (171 seats per flight to 176, main aircraft Boeing 737-900ER then and Boeing 737 MAX 9 now); Delta Air Lines went from 434 kg to 462 kg per passenger (172 seats per flight to 199, main aircraft Boeing 757-200 then and Boeing 767-300ER now).

The airports changed too: JFK to SFO handled 44% of the passengers in 2019 and 52% in 2025.

New York to San Francisco, 2019 and 2025
Measure20192025
Passengers (thousands)4,5073,632
Flights (thousands)30.021.9
Seats filled87%88%
Gallons of fuel per flight6,3477,033
kg CO2 per passenger412414
CO2 per passenger by airline, 2019 and 2025, New York to San FranciscoBar chart of kilograms of CO2 per passenger on New York to San Francisco for each major airline in 2019 and in 2025.0100200300400United Airlines 2019411 kgUnited Airlines 2025414 kgDelta Air Lines 2019434 kgDelta Air Lines 2025462 kgAlaska Airlines 2019333 kgAlaska Airlines 2025296 kgJetBlue 2019384 kgJetBlue 2025350 kg
CO2 per passenger by airline, 2019 and 2025, New York to San FranciscoBar chart of kilograms of CO2 per passenger on New York to San Francisco for each major airline in 2019 and in 2025.0200400United Airlines 2019411 kgUnited Airlines 2025414 kgDelta Air Lines 2019434 kgDelta Air Lines 2025462 kgAlaska Airlines 2019333 kgAlaska Airlines 2025296 kgJetBlue 2019384 kgJetBlue 2025350 kg
Kilograms of CO2 per passenger on the airlines that flew the route in both years. 2019 figures use that year's filings and estimated aircraft fuel rates, with type-average replacements for missing or outlying filings as described in the methodology. Less is better.

New York to San Francisco and back: time in the air

Flights from New York to San Francisco spent 343 minutes in the air on average in 2025, against 293 minutes from San Francisco to New York: 50 minutes longer, 17% more. That's the westbound direction, into the prevailing west-to-east winds, which at flight levels often blow at well over 50 miles an hour.

At this route's average burn of about 1,327 gallons per flight hour, those extra minutes cost about 1,099 gallons per flight, which is about 6.6 gallons or 65 kg of CO2 for each passenger on the slower direction. The route figure above averages both directions.

Time in the air by direction, 2025
DirectionAverage minutes in the airFlights
New York to San Francisco342.910,985
San Francisco to New York293.210,934

Fly or drive

Driving is about 3,016 miles by road, which we estimate as 1.17 times the straight-line distance. An average car emits about 896 kg of CO2 on the trip, at the EPA figure of 0.297 kg per vehicle-mile. Alone, that's 116% more than the 414 kg for a passenger on the flight.

With 3 people in the car, driving comes out lower per person than the flight (299 kg each, and 224 kg each for four). A larger SUV or pickup (0.394 kg per mile) would emit about 1,188 kg per vehicle.

CO2 per person by way of travel, New York to San FranciscoBar chart of kilograms of CO2 per person flying, driving or taking the train between New York and San Francisco.0200400600800Flight, average414 kgCar, driver alone896 kgCar, 2 people448 kgCar, 4 people224 kg
CO2 per person by way of travel, New York to San FranciscoBar chart of kilograms of CO2 per person flying, driving or taking the train between New York and San Francisco.0250500750Flight, average414 kgCar, driver alone896 kgCar, 2 people448 kgCar, 4 people224 kg
CO2 per person, New York to San Francisco. Driving figures divide one car's emissions between the people in it. See flying vs driving for other trip lengths.

Flights are listed under the airline that operates them, so regional flying appears under the regional. How the CO2 and drive figures are worked out is in the methodology.

Routes with shared cities or nearby CO2 per mile

Los Angeles to San Francisco75 kg CO2 per passenger over 337 milesNew York to Miami158 kg CO2 per passenger over 1,082 milesNew York to Orlando141 kg CO2 per passenger over 947 milesNew York to Chicago125 kg CO2 per passenger over 730 milesWashington, DC to Houston193 kg CO2 per passenger over 1,216 milesDallas-Fort Worth to Denver102 kg CO2 per passenger over 644 milesNew York to West Palm Beach166 kg CO2 per passenger over 1,035 milesWashington, DC to Orlando124 kg CO2 per passenger over 770 miles

Airports on this route: John F. Kennedy International Airport, San Francisco International Airport, Newark Liberty International Airport.

Airport and airline references

Source: US Bureau of Transportation Statistics (BTS), T-100 traffic and Schedule T-2 fuel filings; US EPA transport emission factors. See the methodology.

See all routes, or how the airlines compare overall on the airline pages.