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Rankings / Routes / New York to Denver

2025 flights

New York to Denver

Between New York and Denver, 2.7 million passengers flew nonstop in 2025, on 18 thousand flights of about 1,616 miles and 3.5 hours in the air. The average passenger accounted for about 213 kg of CO2 from the fuel burned, from 167 kg on Frontier Airlines to 273 kg on JetBlue.

  • 213 kgCO2 per passenger, average
  • 1,616 milesabout 3.5 hours in the air
  • 2.7 millionpassengers in 2025
  • 86%of seats filled

CO2 per passenger, airline by airline

CO2 per passenger by airline, New York to DenverBar chart of kilograms of CO2 per passenger on each airline between New York and Denver in 2025.0100200Frontier Airlines167 kgUnited Airlines205 kgSouthwest Airlines210 kgDelta Air Lines234 kgJetBlue273 kg
CO2 per passenger by airline, New York to DenverBar chart of kilograms of CO2 per passenger on each airline between New York and Denver in 2025.0100200Frontier Airlines167 kgUnited Airlines205 kgSouthwest Airlines210 kgDelta Air Lines234 kgJetBlue273 kg
Kilograms of CO2 per passenger, one way, 2025. Fuel burned only. Less is better.
New York to Denver by airline, 2025
AirlineShare of passengersFlights (thousands)Main aircraftSeats per flightSeats filledkg CO2 per passenger
United Airlines60%10.3Boeing 737 MAX 8, Boeing 737-900ER17788%205
Delta Air Lines19%3.8Boeing 737-800, Airbus A321neo16582%234
Southwest Airlines14%2.7Boeing 737 MAX 8, Boeing 737-80016783%210
JetBlue5%1.2Airbus A220-300, Airbus A320-20014981%273
Frontier Airlines3%0.4Airbus A320neo, Airbus A321neo20383%167

What explains the differences

It's number 30 of the 100 busiest city pairs by passengers, and number 17 for the lowest CO2 per mile flown (0.13 kg per passenger-mile, number 1 being the lowest). A typical route of 1,616 miles in this set comes out at about 227 kg, so this one is 6.1% below it.

The flights use more than one pair of airports: DEN to LGA (47%), DEN to EWR (38%), DEN to JFK (15%). The figures here cover all of them.

The airlines on this route differ by 63% per passenger. Frontier Airlines burned 2,885 gallons per flight and 168 passengers on each, and JetBlue 3,369 gallons and 120 passengers. Fuel burned per flight explains about 32% of the gap and the number of passengers on each flight the other 68%. Frontier Airlines flew 83% full here against 81% for JetBlue, flying mostly Airbus A320neo against Airbus A220-300.

For comparison, the EPA default factor for a flight of this length (0.129 kg per passenger-mile) would give 208 kg. The EPA figure is a national average for flights of that length. The measured figure for this route is 2.4% higher.

2019 compared with 2025

In 2019 the route carried 2.5 million passengers on 18 thousand flights. In 2025 it carried 2.7 million, up 6%, on 18 thousand flights, up 3%. The average flight had 164 seats then and 172 now, and 88% of them were filled against 86%.

CO2 per passenger was 232 kg in 2019 and 213 kg in 2025, down 8.2%. Fuel burned per flight was down 5.7% (3,424 gallons to 3,229) and passengers per flight were up 2.7% (144 to 148). The distance flown was about the same (1,615 miles then, 1,616 now).

United Airlines led in both years, with 57% of passengers in 2019 and 60% in 2025.

Airline by airline, United Airlines went from 241 kg to 205 kg per passenger (163 seats per flight to 177, main aircraft Airbus A320-200 then and Boeing 737 MAX 8 now); JetBlue went from 205 kg to 273 kg per passenger (192 seats per flight to 149, main aircraft Airbus A321 then and Airbus A220-300 now).

New York to Denver, 2019 and 2025
Measure20192025
Passengers (thousands)2,5482,705
Flights (thousands)17.718.3
Seats filled88%86%
Gallons of fuel per flight3,4243,229
kg CO2 per passenger232213
CO2 per passenger by airline, 2019 and 2025, New York to DenverBar chart of kilograms of CO2 per passenger on New York to Denver for each major airline in 2019 and in 2025.0100200United Airlines 2019241 kgUnited Airlines 2025205 kgDelta Air Lines 2019229 kgDelta Air Lines 2025234 kgSouthwest Airlines 2019224 kgSouthwest Airlines 2025210 kgJetBlue 2019205 kgJetBlue 2025273 kg
CO2 per passenger by airline, 2019 and 2025, New York to DenverBar chart of kilograms of CO2 per passenger on New York to Denver for each major airline in 2019 and in 2025.0100200United Airlines 2019241 kgUnited Airlines 2025205 kgDelta Air Lines 2019229 kgDelta Air Lines 2025234 kgSouthwest Airlines 2019224 kgSouthwest Airlines 2025210 kgJetBlue 2019205 kgJetBlue 2025273 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 Denver and back: time in the air

Flights from New York to Denver spent 228 minutes in the air on average in 2025, against 191 minutes from Denver to New York: 37 minutes longer, 19% 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 927 gallons per flight hour, those extra minutes cost about 572 gallons per flight, which is about 3.9 gallons or 38 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 Denver227.59,174
Denver to New York190.59,162

Fly or drive

Driving is about 1,891 miles by road, which we estimate as 1.17 times the straight-line distance. An average car emits about 562 kg of CO2 on the trip, at the EPA figure of 0.297 kg per vehicle-mile. Alone, that's 163% more than the 213 kg for a passenger on the flight.

With 3 people in the car, driving comes out lower per person than the flight (187 kg each, and 140 kg each for four). A larger SUV or pickup (0.394 kg per mile) would emit about 745 kg per vehicle.

CO2 per person by way of travel, New York to DenverBar chart of kilograms of CO2 per person flying, driving or taking the train between New York and Denver.0200400Flight, average213 kgCar, driver alone562 kgCar, 2 people281 kgCar, 4 people140 kg
CO2 per person by way of travel, New York to DenverBar chart of kilograms of CO2 per person flying, driving or taking the train between New York and Denver.0200400Flight, average213 kgCar, driver alone562 kgCar, 2 people281 kgCar, 4 people140 kg
CO2 per person, New York to Denver. 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 milesChicago to Phoenix190 kg CO2 per passenger over 1,441 milesDenver to Seattle135 kg CO2 per passenger over 1,024 milesDallas-Fort Worth to San Francisco193 kg CO2 per passenger over 1,458 milesLos Angeles to Houston183 kg CO2 per passenger over 1,373 miles

Airports on this route: Denver International Airport, LaGuardia Airport, Newark Liberty International Airport, John F. Kennedy 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.