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Rankings / Routes / Las Vegas to Seattle

2025 flights

Las Vegas to Seattle

Between Las Vegas and Seattle, 1.7 million passengers flew nonstop in 2025, on 12 thousand flights of about 867 miles and 2.1 hours in the air. The average passenger accounted for about 128 kg of CO2 from the fuel burned, from 101 kg on Frontier Airlines to 149 kg on Delta Air Lines.

  • 128 kgCO2 per passenger, average
  • 867 milesabout 2.1 hours in the air
  • 1.7 millionpassengers in 2025
  • 84%of seats filled

CO2 per passenger, airline by airline

CO2 per passenger by airline, Las Vegas to SeattleBar chart of kilograms of CO2 per passenger on each airline between Las Vegas and Seattle in 2025.050100150Frontier Airlines101 kgSpirit Airlines106 kgSouthwest Airlines122 kgAlaska Airlines122 kgDelta Air Lines149 kg
CO2 per passenger by airline, Las Vegas to SeattleBar chart of kilograms of CO2 per passenger on each airline between Las Vegas and Seattle in 2025.050100150Frontier Airlines101 kgSpirit Airlines106 kgSouthwest Airlines122 kgAlaska Airlines122 kgDelta Air Lines149 kg
Kilograms of CO2 per passenger, one way, 2025. Fuel burned only. Less is better.
Las Vegas to Seattle by airline, 2025
AirlineShare of passengersFlights (thousands)Main aircraftSeats per flightSeats filledkg CO2 per passenger
Alaska Airlines46%5.3Boeing 737-900ER, Boeing 737 MAX 917286%122
Delta Air Lines27%3.4Boeing 737-800, Boeing 737-900ER16680%149
Southwest Airlines16%1.9Boeing 737 MAX 8, Boeing 737-70016585%122
Spirit Airlines5%0.6Airbus A320neo, Airbus A321neo19184%106
Frontier Airlines5%0.5Airbus A320neo, Airbus A321neo20883%101

What explains the differences

It's number 92 of the 100 busiest city pairs by passengers, and number 43 for the lowest CO2 per mile flown (0.15 kg per passenger-mile, number 1 being the lowest). A typical route of 867 miles in this set comes out at about 135 kg, so this one is 5.5% below it.

The airlines on this route differ by 48% per passenger. Frontier Airlines burned 1,790 gallons per flight and 173 passengers on each, and Delta Air Lines 2,024 gallons and 133 passengers. Fuel burned per flight explains about 31% of the gap and the number of passengers on each flight the other 69%. Frontier Airlines flew 83% full here against 80% for Delta Air Lines, flying mostly Airbus A320neo against Boeing 737-800.

For comparison, the EPA default factor for a flight of this length (0.129 kg per passenger-mile) would give 112 kg. The EPA figure is a national average for flights of that length. The measured figure for this route is 14% higher.

2019 compared with 2025

In 2019 the route carried 1.9 million passengers on 14 thousand flights. In 2025 it carried 1.7 million, down 13%, on 12 thousand flights, down 17%. The average flight had 161 seats then and 171 now, and 84% of them were filled against 84%.

CO2 per passenger was 137 kg in 2019 and 128 kg in 2025, down 6.8%. Fuel burned per flight was down 2.1% (1,915 gallons to 1,874) and passengers per flight were up 5.0% (136 to 143). The distance flown was about the same (867 miles then, 867 now).

Alaska Airlines led in both years, with 43% of passengers in 2019 and 46% in 2025. Delta Air Lines gained the most share, 23% to 27%. Spirit Airlines lost the most, 20% to 5%. Frontier Airlines didn't have 1% of the passengers in 2019 and now carries 5%.

Airline by airline, Southwest Airlines went from 137 kg to 122 kg per passenger (154 seats per flight to 165, main aircraft Boeing 737-700 then and Boeing 737 MAX 8 now); Delta Air Lines went from 151 kg to 149 kg per passenger (149 seats per flight to 166, main aircraft Boeing 737-800 in both years).

Las Vegas to Seattle, 2019 and 2025
Measure20192025
Passengers (thousands)1,9161,674
Flights (thousands)14.111.7
Seats filled84%84%
Gallons of fuel per flight1,9151,874
kg CO2 per passenger137128
CO2 per passenger by airline, 2019 and 2025, Las Vegas to SeattleBar chart of kilograms of CO2 per passenger on Las Vegas to Seattle for each major airline in 2019 and in 2025.050100150Alaska Airlines 2019136 kgAlaska Airlines 2025122 kgDelta Air Lines 2019151 kgDelta Air Lines 2025149 kgSouthwest Airlines 2019137 kgSouthwest Airlines 2025122 kgSpirit Airlines 2019122 kgSpirit Airlines 2025106 kg
CO2 per passenger by airline, 2019 and 2025, Las Vegas to SeattleBar chart of kilograms of CO2 per passenger on Las Vegas to Seattle for each major airline in 2019 and in 2025.050100150Alaska Airlines 2019136 kgAlaska Airlines 2025122 kgDelta Air Lines 2019151 kgDelta Air Lines 2025149 kgSouthwest Airlines 2019137 kgSouthwest Airlines 2025122 kgSpirit Airlines 2019122 kgSpirit Airlines 2025106 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.

Las Vegas to Seattle and back: time in the air

Flights from Las Vegas to Seattle spent 130 minutes in the air on average in 2025, against 119 minutes from Seattle to Las Vegas: 11 minutes longer, 9% 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 902 gallons per flight hour, those extra minutes cost about 161 gallons per flight, which is about 1.1 gallons or 11 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
Las Vegas to Seattle130.15,845
Seattle to Las Vegas119.45,851

Fly or drive

Driving is about 1,014 miles by road, which we estimate as 1.17 times the straight-line distance. An average car emits about 301 kg of CO2 on the trip, at the EPA figure of 0.297 kg per vehicle-mile. Alone, that's 136% more than the 128 kg for a passenger on the flight.

With 3 people in the car, driving comes out lower per person than the flight (100 kg each, and 75 kg each for four). A larger SUV or pickup (0.394 kg per mile) would emit about 400 kg per vehicle.

CO2 per person by way of travel, Las Vegas to SeattleBar chart of kilograms of CO2 per person flying, driving or taking the train between Las Vegas and Seattle.0100200300Flight, average128 kgCar, driver alone301 kgCar, 2 people151 kgCar, 4 people75 kg
CO2 per person by way of travel, Las Vegas to SeattleBar chart of kilograms of CO2 per person flying, driving or taking the train between Las Vegas and Seattle.0100200300Flight, average128 kgCar, driver alone301 kgCar, 2 people151 kgCar, 4 people75 kg
CO2 per person, Las Vegas to Seattle. 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 Las Vegas53 kg CO2 per passenger over 227 milesLos Angeles to Seattle151 kg CO2 per passenger over 959 milesSan Francisco to Las Vegas71 kg CO2 per passenger over 404 milesSan Francisco to Seattle119 kg CO2 per passenger over 683 milesMiami to Houston142 kg CO2 per passenger over 964 milesOrlando to Boston163 kg CO2 per passenger over 1,111 milesDenver to Minneapolis101 kg CO2 per passenger over 680 milesSeattle to Phoenix164 kg CO2 per passenger over 1,107 miles

Airports on this route: Seattle-Tacoma International Airport, Harry Reid 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.