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Rankings / Routes / Atlanta to Miami

2025 flights

Atlanta to Miami

Between Atlanta and Miami, 4.1 million passengers flew nonstop in 2025, on 25 thousand flights of about 587 miles and 1.4 hours in the air. The average passenger accounted for about 96 kg of CO2 from the fuel burned, from 70 kg on Spirit Airlines to 117 kg on American Airlines.

Delta flies 84% of its Atlanta to Miami flights on the 757-200, a type that averages 26.6 years old in its fleet. Each flight burns 1,769 gallons against 1,302 for Spirit, 36% more, which is why Delta's 101 kg per passenger is 45% above Spirit's 70 kg. Delta carries 62% of the passengers, so the route's 96 kg leans on its number.

The extra fuel isn't spread over more people, either: Delta's flights carry 170 passengers and Spirit's 181.

  • 96 kgCO2 per passenger, average
  • 587 milesabout 1.4 hours in the air
  • 4.1 millionpassengers in 2025
  • 84%of seats filled

CO2 per passenger, airline by airline

CO2 per passenger by airline, Atlanta to MiamiBar chart of kilograms of CO2 per passenger on each airline between Atlanta and Miami in 2025.0255075100Spirit Airlines70 kgFrontier Airlines74 kgSouthwest Airlines97 kgDelta Air Lines101 kgAmerican Airlines117 kg
CO2 per passenger by airline, Atlanta to MiamiBar chart of kilograms of CO2 per passenger on each airline between Atlanta and Miami in 2025.050100Spirit Airlines70 kgFrontier Airlines74 kgSouthwest Airlines97 kgDelta Air Lines101 kgAmerican Airlines117 kg
Kilograms of CO2 per passenger, one way, 2025. Fuel burned only. Less is better.
Atlanta to Miami by airline, 2025
AirlineShare of passengersFlights (thousands)Main aircraftSeats per flightSeats filledkg CO2 per passenger
Delta Air Lines62%14.8Boeing 757-200, Airbus A32119985%101
Spirit Airlines15%3.3Airbus A321neo, Airbus A32120788%70
Frontier Airlines10%2.5Airbus A320neo, Airbus A321neo20880%74
American Airlines10%3.2Airbus A319, Boeing 737-80015777%117
Southwest Airlines2%0.6Boeing 737 MAX 8, Boeing 737-80016774%97

What explains the differences

It's number 12 of the 100 busiest city pairs by passengers, and number 63 for the lowest CO2 per mile flown (0.16 kg per passenger-mile, number 1 being the lowest). A typical route of 587 miles in this set comes out at about 101 kg, so this one is 4.8% below it.

The flights use more than one pair of airports: ATL to FLL (54%), ATL to MIA (46%). The figures here cover all of them.

The airlines on this route differ by 67% per passenger. Spirit Airlines burned 1,302 gallons per flight and 181 passengers on each, and American Airlines 1,450 gallons and 121 passengers. Fuel burned per flight explains about 21% of the gap and the number of passengers on each flight the other 79%. Spirit Airlines flew 88% full here against 77% for American Airlines, flying mostly Airbus A321neo against Airbus A319.

For comparison, the EPA default factor for a flight of this length (0.129 kg per passenger-mile) would give 76 kg. The EPA figure is a national average for flights of that length. The measured figure for this route is 27% higher.

2019 compared with 2025

In 2019 the route carried 4.6 million passengers on 31 thousand flights. In 2025 it carried 4.1 million, down 11%, on 25 thousand flights, down 19%. The average flight had 168 seats then and 192 now, and 88% of them were filled against 84%.

CO2 per passenger was 100 kg in 2019 and 96 kg in 2025, down 4.2%. Fuel burned per flight was up 4.8% (1,512 gallons to 1,583) and passengers per flight were up 9.4% (147 to 161). The distance flown was about the same (587 miles then, 587 now).

Delta Air Lines led in both years, with 62% of passengers in 2019 and 62% in 2025. Frontier Airlines gained the most share, 2% to 10%. Southwest Airlines lost the most, 9% to 2%. JetBlue and Republic Airways no longer reach 1% of passengers, having had 5% in 2019.

Airline by airline, Spirit Airlines went from 89 kg to 70 kg per passenger (177 seats per flight to 207, main aircraft Airbus A319 then and Airbus A321neo now); Delta Air Lines went from 99 kg to 101 kg per passenger (181 seats per flight to 199, main aircraft Boeing 757-200 in both years).

The airports changed too: ATL to FLL handled 60% of the passengers in 2019 and 54% in 2025.

Atlanta to Miami, 2019 and 2025
Measure20192025
Passengers (thousands)4,5924,065
Flights (thousands)31.225.3
Seats filled88%84%
Gallons of fuel per flight1,5121,583
kg CO2 per passenger10096
CO2 per passenger by airline, 2019 and 2025, Atlanta to MiamiBar chart of kilograms of CO2 per passenger on Atlanta to Miami for each major airline in 2019 and in 2025.050100Delta Air Lines 201999 kgDelta Air Lines 2025101 kgSpirit Airlines 201989 kgSpirit Airlines 202570 kgFrontier Airlines 201973 kgFrontier Airlines 202574 kgAmerican Airlines 2019118 kgAmerican Airlines 2025117 kg
CO2 per passenger by airline, 2019 and 2025, Atlanta to MiamiBar chart of kilograms of CO2 per passenger on Atlanta to Miami for each major airline in 2019 and in 2025.050100Delta Air Lines 201999 kgDelta Air Lines 2025101 kgSpirit Airlines 201989 kgSpirit Airlines 202570 kgFrontier Airlines 201973 kgFrontier Airlines 202574 kgAmerican Airlines 2019118 kgAmerican Airlines 2025117 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.

Atlanta to Miami and back: time in the air

The time in the air is almost the same each way: 86 minutes on average from Atlanta to Miami and 87 minutes back. A difference of 1 minute is within what routing and congestion alone produce.

Time in the air by direction, 2025
DirectionAverage minutes in the airFlights
Miami to Atlanta87.012,636
Atlanta to Miami86.212,620

Fly or drive

Driving is about 687 miles by road, which we estimate as 1.17 times the straight-line distance. An average car emits about 204 kg of CO2 on the trip, at the EPA figure of 0.297 kg per vehicle-mile. Alone, that's 113% more than the 96 kg for a passenger on the flight.

With 3 people in the car, driving comes out lower per person than the flight (68 kg each, and 51 kg each for four). A larger SUV or pickup (0.394 kg per mile) would emit about 271 kg per vehicle.

CO2 per person by way of travel, Atlanta to MiamiBar chart of kilograms of CO2 per person flying, driving or taking the train between Atlanta and Miami.050100150200Flight, average96 kgCar, driver alone204 kgCar, 2 people102 kgCar, 4 people51 kg
CO2 per person by way of travel, Atlanta to MiamiBar chart of kilograms of CO2 per person flying, driving or taking the train between Atlanta and Miami.0100200Flight, average96 kgCar, driver alone204 kgCar, 2 people102 kgCar, 4 people51 kg
CO2 per person, Atlanta to Miami. 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.

What to take from it

Spirit's figure on this route fell from 89 kg in 2019 to 70 kg, while the A321neo became 37% of its flights here. Frontier is next at 74 kg. American, on A319s and 737-800s, is the highest at 117 kg.

'Miami' is really two airports, and Fort Lauderdale takes 54% of the passengers, more than Miami itself. Passengers are 11% below 2019. At 687 road miles, a car with four people comes to 51 kg each, 47% below the flight, and the wind makes no difference to flight time.

Routes with shared cities or nearby CO2 per mile

New York to Miami158 kg CO2 per passenger over 1,082 milesNew York to Atlanta124 kg CO2 per passenger over 758 milesAtlanta to Washington, DC104 kg CO2 per passenger over 554 milesMiami to Washington, DC144 kg CO2 per passenger over 921 milesWashington, DC to Orlando124 kg CO2 per passenger over 770 milesChicago to Boston140 kg CO2 per passenger over 861 milesNew York to Los Angeles406 kg CO2 per passenger over 2,465 miles

Airports on this route: Hartsfield-Jackson Atlanta International Airport, Fort Lauderdale-Hollywood, Miami 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.