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Rankings / Routes / New York to Boston

2025 flights

New York to Boston

Between New York and Boston, 2.4 million passengers flew nonstop in 2025, on 34 thousand flights of about 187 miles and 44 minutes in the air. The average passenger accounted for about 76 kg of CO2 from the fuel burned, from 60 kg on United Airlines to 83 kg on Republic Airways.

  • 76 kgCO2 per passenger, average
  • 187 milesabout 44 minutes in the air
  • 2.4 millionpassengers in 2025
  • 70%of seats filled

CO2 per passenger, airline by airline

CO2 per passenger by airline, New York to BostonBar chart of kilograms of CO2 per passenger on each airline between New York and Boston in 2025.020406080United Airlines60 kgDelta Air Lines62 kgJetBlue82 kgRepublic Airways83 kg
CO2 per passenger by airline, New York to BostonBar chart of kilograms of CO2 per passenger on each airline between New York and Boston in 2025.0255075United Airlines60 kgDelta Air Lines62 kgJetBlue82 kgRepublic Airways83 kg
Kilograms of CO2 per passenger, one way, 2025. Fuel burned only. Less is better.
New York to Boston by airline, 2025
AirlineShare of passengersFlights (thousands)Main aircraftSeats per flightSeats filledkg CO2 per passenger
Republic Airways46%18.7Embraer 1757577%83
United Airlines24%5.0Airbus A319, Boeing 737 MAX 816072%60
JetBlue22%6.6Airbus A220-300, Airbus A320-20013658%82
Delta Air Lines6%1.9Airbus A220-30011571%62

What explains the differences

It's number 51 of the 100 busiest city pairs by passengers, and number 100 for the lowest CO2 per mile flown (0.41 kg per passenger-mile, number 1 being the lowest). A typical route of 187 miles in this set comes out at about 52 kg, so this one is 47% above it.

The flights use more than one pair of airports: BOS to LGA (35%), BOS to JFK (33%), BOS to EWR (29%). The figures here cover all of them.

The airlines on this route differ by 37% per passenger. United Airlines burned 712 gallons per flight and 115 passengers on each, and Republic Airways 494 gallons and 58 passengers. The gap comes from how many passengers share each flight, not from fuel burned per flight. United Airlines flew 72% full here against 77% for Republic Airways, flying mostly Airbus A319 against Embraer 175.

For comparison, the EPA default factor for a flight of this length (0.207 kg per passenger-mile) would give 39 kg. The EPA figure is a national average for flights of that length. The measured figure for this route is 96% higher.

2019 compared with 2025

In 2019 the route carried 3.2 million passengers on 45 thousand flights. In 2025 it carried 2.4 million, down 26%, on 34 thousand flights, down 24%. The average flight had 102 seats then and 99 now, and 71% of them were filled against 70%.

CO2 per passenger was 79 kg in 2019 and 76 kg in 2025, down 4.1%. Fuel burned per flight was down 6.7% (583 gallons to 544) and passengers per flight were down 2.7% (72 to 70). The distance flown was about the same (188 miles then, 187 now).

United Airlines had the most passengers in 2019 (25%) and Republic Airways in 2025 (46%). Delta Air Lines lost the most, 14% to 6%. American Airlines and Endeavor Air and SkyWest Airlines and CommuteAir no longer reach 1% of passengers, having had 26% in 2019.

Airline by airline, Delta Air Lines went from 70 kg to 62 kg per passenger (121 seats per flight to 115, main aircraft Airbus A319 then and Airbus A220-300 now); United Airlines went from 60 kg to 60 kg per passenger (152 seats per flight to 160, main aircraft Airbus A320-200 then and Airbus A319 now).

The airports changed too: BOS to LGA handled 40% of the passengers in 2019 and 35% in 2025.

New York to Boston, 2019 and 2025
Measure20192025
Passengers (thousands)3,2072,378
Flights (thousands)44.734.1
Seats filled71%70%
Gallons of fuel per flight583544
kg CO2 per passenger7976
CO2 per passenger by airline, 2019 and 2025, New York to BostonBar chart of kilograms of CO2 per passenger on New York to Boston for each major airline in 2019 and in 2025.020406080Republic Airways 201992 kgRepublic Airways 202583 kgUnited Airlines 201960 kgUnited Airlines 202560 kgJetBlue 201990 kgJetBlue 202582 kgDelta Air Lines 201970 kgDelta Air Lines 202562 kg
CO2 per passenger by airline, 2019 and 2025, New York to BostonBar chart of kilograms of CO2 per passenger on New York to Boston for each major airline in 2019 and in 2025.0255075Republic Airways 201992 kgRepublic Airways 202583 kgUnited Airlines 201960 kgUnited Airlines 202560 kgJetBlue 201990 kgJetBlue 202582 kgDelta Air Lines 201970 kgDelta Air Lines 202562 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 Boston and back: time in the air

Flights from Boston to New York spent 48 minutes in the air on average in 2025, against 41 minutes from New York to Boston: 8 minutes longer, 18% more. The route runs mostly north to south, so the winds on the day, routing and congestion decide the difference.

At this route's average burn of about 735 gallons per flight hour, those extra minutes cost about 92 gallons per flight, which is about 1.3 gallons or 13 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
Boston to New York48.117,058
New York to Boston40.617,013

Fly or drive

Driving is about 219 miles by road, which we estimate as 1.17 times the straight-line distance. An average car emits about 65 kg of CO2 on the trip, at the EPA figure of 0.297 kg per vehicle-mile. Alone, that's 15% less than the 76 kg for a passenger on the flight.

Driving alone already beats the flight on CO2 here, but it takes about 3.6 hours of driving at 60 miles an hour against 44 minutes in the air.

A direct Amtrak train serves both cities. Using the EPA figure for the Northeast Corridor (0.023 kg per passenger-mile, mostly electric) and a rail distance about equal to the road distance, a train passenger would account for roughly 5 kg, 93% less than the flight.

CO2 per person by way of travel, New York to BostonBar chart of kilograms of CO2 per person flying, driving or taking the train between New York and Boston.020406080Flight, average76 kgCar, driver alone65 kgCar, 2 people32 kgCar, 4 people16 kgTrain5 kg
CO2 per person by way of travel, New York to BostonBar chart of kilograms of CO2 per person flying, driving or taking the train between New York and Boston.0255075Flight, average76 kgCar, driver alone65 kgCar, 2 people32 kgCar, 4 people16 kgTrain5 kg
CO2 per person, New York to Boston. 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

New 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 milesNew York to Atlanta124 kg CO2 per passenger over 758 milesHonolulu to Kahului39 kg CO2 per passenger over 100 milesNew York to Washington, DC86 kg CO2 per passenger over 215 miles

Airports on this route: LaGuardia Airport, John F. Kennedy 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.