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Rankings / Routes / Honolulu to Kahului

2025 flights

Honolulu to Kahului

Between Honolulu and Kahului, 2.0 million passengers flew nonstop in 2025, on 21 thousand flights of about 100 miles and 23 minutes in the air. The average passenger accounted for about 39 kg of CO2 from the fuel burned, from 34 kg on Southwest Airlines to 41 kg on Hawaiian Airlines.

  • 39 kgCO2 per passenger, average
  • 100 milesabout 23 minutes in the air
  • 2.0 millionpassengers in 2025
  • 67%of seats filled

CO2 per passenger, airline by airline

CO2 per passenger by airline, Honolulu to KahuluiBar chart of kilograms of CO2 per passenger on each airline between Honolulu and Kahului in 2025.010203040Southwest Airlines34 kgHawaiian Airlines41 kg
CO2 per passenger by airline, Honolulu to KahuluiBar chart of kilograms of CO2 per passenger on each airline between Honolulu and Kahului in 2025.02040Southwest Airlines34 kgHawaiian Airlines41 kg
Kilograms of CO2 per passenger, one way, 2025. Fuel burned only. Less is better.
Honolulu to Kahului by airline, 2025
AirlineShare of passengersFlights (thousands)Main aircraftSeats per flightSeats filledkg CO2 per passenger
Hawaiian Airlines72%15.0Airbus A321neo12976%41
Southwest Airlines28%6.3Boeing 737 MAX 8, Boeing 737-80017551%34

What explains the differences

It's number 66 of the 100 busiest city pairs by passengers, and number 98 for the lowest CO2 per mile flown (0.39 kg per passenger-mile, number 1 being the lowest). A typical route of 100 miles in this set comes out at about 41 kg, so this one is 4.7% below it.

The airlines on this route differ by 18% per passenger. Southwest Airlines burned 315 gallons per flight and 89 passengers on each, and Hawaiian Airlines 408 gallons and 98 passengers. The gap comes from fuel burned per flight, a little of it offset by passengers per flight. Southwest Airlines flew 51% full here against 76% for Hawaiian Airlines, flying mostly Boeing 737 MAX 8 against Airbus A321neo.

For comparison, the EPA default factor for a flight of this length (0.207 kg per passenger-mile) would give 21 kg. The EPA figure is a national average for flights of that length. The measured figure for this route is 88% higher.

2019 compared with 2025

In 2019 the route carried 2.1 million passengers on 23 thousand flights. In 2025 it carried 2.0 million, down 3%, on 21 thousand flights, down 8%. The average flight had 124 seats then and 142 now, and 73% of them were filled against 67%.

CO2 per passenger was 39 kg in 2019 and 39 kg in 2025, down 1.1%. Fuel burned per flight was up 3.5% (368 gallons to 381) and passengers per flight were up 4.7% (91 to 95). The distance flown was about the same (100 miles then, 100 now).

Hawaiian Airlines led in both years, with 87% of passengers in 2019 and 72% in 2025. Southwest Airlines gained the most share, 12% to 28%. Hawaiian Airlines lost the most, 87% to 72%.

Airline by airline, Hawaiian Airlines went from 41 kg to 41 kg per passenger (128 seats per flight to 129, main aircraft Airbus A321neo in both years); Southwest Airlines went from 26 kg to 34 kg per passenger (175 seats per flight to 175, main aircraft Boeing 737-800 then and Boeing 737 MAX 8 now).

Honolulu to Kahului, 2019 and 2025
Measure20192025
Passengers (thousands)2,1002,028
Flights (thousands)23.021.2
Seats filled73%67%
Gallons of fuel per flight368381
kg CO2 per passenger3939
CO2 per passenger by airline, 2019 and 2025, Honolulu to KahuluiBar chart of kilograms of CO2 per passenger on Honolulu to Kahului for each major airline in 2019 and in 2025.010203040Hawaiian Airlines 201941 kgHawaiian Airlines 202541 kgSouthwest Airlines 201926 kgSouthwest Airlines 202534 kg
CO2 per passenger by airline, 2019 and 2025, Honolulu to KahuluiBar chart of kilograms of CO2 per passenger on Honolulu to Kahului for each major airline in 2019 and in 2025.02040Hawaiian Airlines 201941 kgHawaiian Airlines 202541 kgSouthwest Airlines 201926 kgSouthwest Airlines 202534 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.

Honolulu to Kahului and back: time in the air

The time in the air is almost the same each way: 22 minutes on average from Honolulu to Kahului and 25 minutes back. A difference of 3 minutes is within what routing and congestion alone produce.

Time in the air by direction, 2025
DirectionAverage minutes in the airFlights
Kahului to Honolulu24.610,627
Honolulu to Kahului21.910,621

Fly or drive

There's no road between Honolulu and Kahului, so the choice is a flight or a boat, and a flight is the only practical option for most trips.

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 Honolulu321 kg CO2 per passenger over 2,560 milesSan Francisco to Honolulu300 kg CO2 per passenger over 2,404 milesDallas-Fort Worth to Austin51 kg CO2 per passenger over 190 milesDallas-Fort Worth to Houston67 kg CO2 per passenger over 233 milesNew York to Washington, DC86 kg CO2 per passenger over 215 milesNew York to Boston76 kg CO2 per passenger over 187 miles

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.