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Rankings / Routes / Orlando to Houston

2025 flights

Orlando to Houston

Between Orlando and Houston, 1.6 million passengers flew nonstop in 2025, on 11 thousand flights of about 852 miles and 2.0 hours in the air. The average passenger accounted for about 117 kg of CO2 from the fuel burned, from 98 kg on Frontier Airlines to 127 kg on United Airlines.

  • 117 kgCO2 per passenger, average
  • 852 milesabout 2.0 hours in the air
  • 1.6 millionpassengers in 2025
  • 84%of seats filled

CO2 per passenger, airline by airline

CO2 per passenger by airline, Orlando to HoustonBar chart of kilograms of CO2 per passenger on each airline between Orlando and Houston in 2025.050100Frontier Airlines98 kgSpirit Airlines99 kgSouthwest Airlines118 kgUnited Airlines127 kg
CO2 per passenger by airline, Orlando to HoustonBar chart of kilograms of CO2 per passenger on each airline between Orlando and Houston in 2025.050100Frontier Airlines98 kgSpirit Airlines99 kgSouthwest Airlines118 kgUnited Airlines127 kg
Kilograms of CO2 per passenger, one way, 2025. Fuel burned only. Less is better.
Orlando to Houston by airline, 2025
AirlineShare of passengersFlights (thousands)Main aircraftSeats per flightSeats filledkg CO2 per passenger
United Airlines43%4.7Boeing 737-900ER18084%127
Southwest Airlines32%3.9Boeing 737 MAX 8, Boeing 737-70016483%118
Spirit Airlines15%1.4Airbus A321, Airbus A321neo20786%99
Frontier Airlines10%0.9Airbus A321neo, Airbus A320neo22081%98

What explains the differences

It's number 94 of the 100 busiest city pairs by passengers, and number 27 for the lowest CO2 per mile flown (0.14 kg per passenger-mile, number 1 being the lowest). A typical route of 852 miles in this set comes out at about 133 kg, so this one is 12% below it.

The flights use more than one pair of airports: IAH to MCO (68%), HOU to MCO (32%). The figures here cover all of them.

The airlines on this route differ by 30% per passenger. Frontier Airlines burned 1,783 gallons per flight and 178 passengers on each, and United Airlines 1,973 gallons and 151 passengers. Fuel burned per flight explains about 38% of the gap and the number of passengers on each flight the other 62%. Frontier Airlines flew 81% full here against 84% 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 110 kg. The EPA figure is a national average for flights of that length. The measured figure for this route is 6.5% higher.

2019 compared with 2025

In 2019 the route carried 1.5 million passengers on 10 thousand flights. In 2025 it carried 1.6 million, up 10%, on 11 thousand flights, up 12%. The average flight had 175 seats then and 181 now, and 88% of them were filled against 84%.

CO2 per passenger was 122 kg in 2019 and 117 kg in 2025, down 3.8%. Fuel burned per flight was down 5.5% (1,929 gallons to 1,823) and passengers per flight were down 1.8% (155 to 152). The distance flown was about the same (852 miles then, 852 now).

United Airlines led in both years, with 48% of passengers in 2019 and 43% in 2025. Frontier Airlines gained the most share, 2% to 10%. United Airlines lost the most, 48% to 43%.

Airline by airline, Spirit Airlines went from 116 kg to 99 kg per passenger (223 seats per flight to 207, main aircraft Airbus A321 in both years); United Airlines went from 126 kg to 127 kg per passenger (170 seats per flight to 180, main aircraft Boeing 737-900ER in both years).

Orlando to Houston, 2019 and 2025
Measure20192025
Passengers (thousands)1,4911,647
Flights (thousands)9.610.8
Seats filled88%84%
Gallons of fuel per flight1,9291,823
kg CO2 per passenger122117
CO2 per passenger by airline, 2019 and 2025, Orlando to HoustonBar chart of kilograms of CO2 per passenger on Orlando to Houston for each major airline in 2019 and in 2025.050100United Airlines 2019126 kgUnited Airlines 2025127 kgSouthwest Airlines 2019121 kgSouthwest Airlines 2025118 kgSpirit Airlines 2019116 kgSpirit Airlines 202599 kgFrontier Airlines 2019105 kgFrontier Airlines 202598 kg
CO2 per passenger by airline, 2019 and 2025, Orlando to HoustonBar chart of kilograms of CO2 per passenger on Orlando to Houston for each major airline in 2019 and in 2025.050100United Airlines 2019126 kgUnited Airlines 2025127 kgSouthwest Airlines 2019121 kgSouthwest Airlines 2025118 kgSpirit Airlines 2019116 kgSpirit Airlines 202599 kgFrontier Airlines 2019105 kgFrontier Airlines 202598 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.

Orlando to Houston and back: time in the air

Flights from Orlando to Houston spent 126 minutes in the air on average in 2025, against 111 minutes from Houston to Orlando: 15 minutes longer, 13% 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 923 gallons per flight hour, those extra minutes cost about 229 gallons per flight, which is about 1.5 gallons or 15 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
Orlando to Houston125.95,441
Houston to Orlando111.05,408

Fly or drive

Driving is about 997 miles by road, which we estimate as 1.17 times the straight-line distance. An average car emits about 296 kg of CO2 on the trip, at the EPA figure of 0.297 kg per vehicle-mile. Alone, that's 153% more than the 117 kg for a passenger on the flight.

With 3 people in the car, driving comes out lower per person than the flight (99 kg each, and 74 kg each for four). A larger SUV or pickup (0.394 kg per mile) would emit about 393 kg per vehicle.

CO2 per person by way of travel, Orlando to HoustonBar chart of kilograms of CO2 per person flying, driving or taking the train between Orlando and Houston.0100200300Flight, average117 kgCar, driver alone296 kgCar, 2 people148 kgCar, 4 people74 kg
CO2 per person by way of travel, Orlando to HoustonBar chart of kilograms of CO2 per person flying, driving or taking the train between Orlando and Houston.0100200300Flight, average117 kgCar, driver alone296 kgCar, 2 people148 kgCar, 4 people74 kg
CO2 per person, Orlando 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

New York to Orlando141 kg CO2 per passenger over 947 milesWashington, DC to Orlando124 kg CO2 per passenger over 770 milesAtlanta to Orlando71 kg CO2 per passenger over 404 milesLos Angeles to Houston183 kg CO2 per passenger over 1,373 milesAtlanta to Denver165 kg CO2 per passenger over 1,199 milesChicago to Orlando137 kg CO2 per passenger over 1,000 milesDallas-Fort Worth to Las Vegas148 kg CO2 per passenger over 1,059 milesLos Angeles to Dallas-Fort Worth171 kg CO2 per passenger over 1,222 miles

Airports on this route: George Bush Intercontinental Airport, Orlando 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.