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Rankings / Routes / Las Vegas to Houston

2025 flights

Las Vegas to Houston

Between Las Vegas and Houston, 1.6 million passengers flew nonstop in 2025, on 11 thousand flights of about 1,227 miles and 2.7 hours in the air. The average passenger accounted for about 164 kg of CO2 from the fuel burned, from 135 kg on Frontier Airlines to 178 kg on United Airlines.

  • 164 kgCO2 per passenger, average
  • 1,227 milesabout 2.7 hours in the air
  • 1.6 millionpassengers in 2025
  • 80%of seats filled

CO2 per passenger, airline by airline

CO2 per passenger by airline, Las Vegas to HoustonBar chart of kilograms of CO2 per passenger on each airline between Las Vegas and Houston in 2025.050100150Frontier Airlines135 kgSpirit Airlines139 kgSouthwest Airlines161 kgUnited Airlines178 kg
CO2 per passenger by airline, Las Vegas to HoustonBar chart of kilograms of CO2 per passenger on each airline between Las Vegas and Houston in 2025.050100150Frontier Airlines135 kgSpirit Airlines139 kgSouthwest Airlines161 kgUnited Airlines178 kg
Kilograms of CO2 per passenger, one way, 2025. Fuel burned only. Less is better.
Las Vegas to Houston by airline, 2025
AirlineShare of passengersFlights (thousands)Main aircraftSeats per flightSeats filledkg CO2 per passenger
United Airlines44%5.2Boeing 737-900ER17679%178
Southwest Airlines35%4.1Boeing 737 MAX 8, Boeing 737-80016881%161
Spirit Airlines15%1.5Airbus A320neo, Airbus A32119984%139
Frontier Airlines5%0.5Airbus A321neo, Airbus A320neo21379%135

What explains the differences

It's number 99 of the 100 busiest city pairs by passengers, and number 20 for the lowest CO2 per mile flown (0.13 kg per passenger-mile, number 1 being the lowest). A typical route of 1,227 miles in this set comes out at about 179 kg, so this one is 8.6% below it.

The flights use more than one pair of airports: IAH to LAS (65%), HOU to LAS (35%). The figures here cover all of them.

The airlines on this route differ by 32% per passenger. Frontier Airlines burned 2,333 gallons per flight and 169 passengers on each, and United Airlines 2,530 gallons and 139 passengers. Fuel burned per flight explains about 29% of the gap and the number of passengers on each flight the other 71%. Frontier Airlines flew 79% full here against 79% for United Airlines, flying mostly Airbus A321neo against Boeing 737-900ER.

For comparison, the EPA default factor for a flight of this length (0.129 kg per passenger-mile) would give 158 kg. The EPA figure is a national average for flights of that length. The measured figure for this route is 3.5% higher.

2019 compared with 2025

In 2019 the route carried 1.4 million passengers on 10 thousand flights. In 2025 it carried 1.6 million, up 12%, on 11 thousand flights, up 17%. The average flight had 168 seats then and 178 now, and 89% of them were filled against 80%.

CO2 per passenger was 162 kg in 2019 and 164 kg in 2025, up 0.9%. Fuel burned per flight was down 3.7% (2,493 gallons to 2,399) and passengers per flight were down 4.6% (150 to 143). The distance flown was about the same (1,227 miles then, 1,227 now).

United Airlines led in both years, with 44% of passengers in 2019 and 44% in 2025. Spirit Airlines lost the most, 18% to 15%.

Airline by airline, Spirit Airlines went from 148 kg to 139 kg per passenger (202 seats per flight to 199, main aircraft Airbus A321 then and Airbus A320neo now); United Airlines went from 172 kg to 178 kg per passenger (162 seats per flight to 176, main aircraft Boeing 737-900ER in both years).

Las Vegas to Houston, 2019 and 2025
Measure20192025
Passengers (thousands)1,4441,611
Flights (thousands)9.711.3
Seats filled89%80%
Gallons of fuel per flight2,4932,399
kg CO2 per passenger162164
CO2 per passenger by airline, 2019 and 2025, Las Vegas to HoustonBar chart of kilograms of CO2 per passenger on Las Vegas to Houston for each major airline in 2019 and in 2025.050100150United Airlines 2019172 kgUnited Airlines 2025178 kgSouthwest Airlines 2019161 kgSouthwest Airlines 2025161 kgSpirit Airlines 2019148 kgSpirit Airlines 2025139 kgFrontier Airlines 2019131 kgFrontier Airlines 2025135 kg
CO2 per passenger by airline, 2019 and 2025, Las Vegas to HoustonBar chart of kilograms of CO2 per passenger on Las Vegas to Houston for each major airline in 2019 and in 2025.050100150United Airlines 2019172 kgUnited Airlines 2025178 kgSouthwest Airlines 2019161 kgSouthwest Airlines 2025161 kgSpirit Airlines 2019148 kgSpirit Airlines 2025139 kgFrontier Airlines 2019131 kgFrontier Airlines 2025135 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 Houston and back: time in the air

Flights from Houston to Las Vegas spent 169 minutes in the air on average in 2025, against 151 minutes from Las Vegas to Houston: 18 minutes longer, 12% 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 271 gallons per flight, which is about 1.9 gallons or 18 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
Houston to Las Vegas168.65,658
Las Vegas to Houston150.65,627

Fly or drive

Driving is about 1,436 miles by road, which we estimate as 1.17 times the straight-line distance. An average car emits about 426 kg of CO2 on the trip, at the EPA figure of 0.297 kg per vehicle-mile. Alone, that's 160% more than the 164 kg for a passenger on the flight.

With 3 people in the car, driving comes out lower per person than the flight (142 kg each, and 107 kg each for four). A larger SUV or pickup (0.394 kg per mile) would emit about 566 kg per vehicle.

CO2 per person by way of travel, Las Vegas to HoustonBar chart of kilograms of CO2 per person flying, driving or taking the train between Las Vegas and Houston.0100200300400Flight, average164 kgCar, driver alone426 kgCar, 2 people213 kgCar, 4 people107 kg
CO2 per person by way of travel, Las Vegas to HoustonBar chart of kilograms of CO2 per person flying, driving or taking the train between Las Vegas and Houston.0200400Flight, average164 kgCar, driver alone426 kgCar, 2 people213 kgCar, 4 people107 kg
CO2 per person, Las Vegas to Houston. 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 milesSan Francisco to Las Vegas71 kg CO2 per passenger over 404 milesLos Angeles to Houston183 kg CO2 per passenger over 1,373 milesNew York to Houston197 kg CO2 per passenger over 1,412 milesDallas-Fort Worth to San Francisco193 kg CO2 per passenger over 1,458 milesLos Angeles to Atlanta261 kg CO2 per passenger over 1,937 milesChicago to Miami161 kg CO2 per passenger over 1,187 miles

Airports on this route: George Bush Intercontinental Airport, Harry Reid International Airport, William P. Hobby 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.