Frontier Airlines

The story in the figures

Frontier Airlines' passenger-miles per gallon rose 99% between 2000 and 2025, from 41.6 to 83.0. Most of that came from the aircraft: seat-miles per gallon rose 64%, while planes ran fuller, with 65% of seat-miles filled in 2000 against 78% in 2025.

The shape of the flying changed as well: the average flight went from 131 seats to 209. In general, larger aircraft spread fuel over more passengers.

Its best year was 2023, at 84.0 passenger-miles per gallon, and its latest figure sits 1.3% below that.

In 2020 the pandemic emptied the cabins: load factor dropped from 86% to 67%, and passenger-miles per gallon fell from 83.9 to 70.5. A flight burns most of its fuel whether the seats are full or not, which is why an empty year looks so bad per passenger. By 2025 the figure was 1.1% below its 2019 level.

Against the all-airline figure for 2025 (60.6), Frontier Airlines was 37% better. On a 1,000 mile trip that works out to 118 kg of CO2 for one passenger, from burning jet fuel only.

What one seat costs the climate

CO2 for one passenger on Frontier Airlines, from burning jet fuel only.

• 59 kgover 500 miles
• 118 kgover 1,000 miles
• 235 kgover 2,000 miles

Year-by-year figures

Year	Passenger-miles per gallon	kg CO2 per passenger-mile	Seat-miles per gallon	Load factor	Passengers (millions)	Fuel (million gallons)	CO2 (thousand tonnes)
2025	83.0	0.118	105.7	78.5%	33.2	376	3,661
2024	80.2	0.122	104.4	76.8%	33.3	381	3,719
2023	84.0	0.116	103.2	81.4%	30.2	366	3,569
2022	82.2	0.119	101.6	80.9%	25.5	312	3,043
2021	76.7	0.127	101.1	75.8%	20.7	266	2,589
2020	70.5	0.138	104.4	67.5%	11.2	162	1,582
2019	83.9	0.116	97.4	86.1%	22.8	288	2,809
2018	80.0	0.122	93.6	85.4%	19.8	261	2,546
2017	78.2	0.125	90.5	86.4%	17.0	242	2,358
2016	74.2	0.131	85.1	87.2%	14.8	214	2,086
2015	68.5	0.142	79.0	86.7%	12.6	183	1,789
2014	67.5	0.144	75.5	89.5%	11.7	154	1,499
2013	67.9	0.144	74.4	91.3%	10.3	135	1,313
2012	68.3	0.143	76.3	89.4%	10.4	146	1,426
2011*	65.3	0.149	74.9	87.1%	10.7	158*	1,539*
2010*	60.8	0.160	72.7	83.6%	9.3	152*	1,478*
2009	56.1	0.174	69.1	81.1%	9.4	152	1,486
2008	54.9	0.178	67.0	81.9%	10.6	180	1,752
2007	49.9	0.195	63.5	78.6%	10.5	197	1,924
2006	48.8	0.200	61.2	79.7%	8.9	171	1,663
2005	47.9	0.203	60.4	79.3%	7.5	151	1,473
2004	45.0	0.217	61.2	73.5%	6.5	140	1,363
2003	47.1	0.207	68.3	69.0%	5.3	99	966
2002	43.6	0.224	73.2	59.5%	3.8	77	755
2001	39.2	0.249	64.8	60.6%	3.1	69	674
2000	41.6	0.234	64.5	64.5%	3.1	64	626

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The Frontier Airlines fleet

Frontier Airlines operated 176 passenger aircraft of its own in 2025. The average age was 4.6 years: 51% of the aircraft were under five years old and 0% were twenty or older. The oldest was an Airbus A320 built in 2015. That's the 2nd youngest of the 12 airlines ranked here.

In 2006 the average age was 2.5 years across 55 aircraft. It's older now by 2.1 years, and the fleet is bigger.

On the Airbus A320neo, Frontier Airlines fits 186 seats on average, against a median of 176 at the other airlines that fly it (176 to 176). Seats on the same aircraft are one reason fuel per seat and fuel per passenger differ between airlines: the fuel burned by a given plane is much the same, and more seats share it.

Frontier Airlines aircraft by model, 2025

Model	Aircraft	Average seats	Other airlines, median seats	Average age
Airbus A320neo	82	186	176	5.9
Airbus A321neo	67	234	194	1.1
Airbus A321	21	230	191	8.8
Other models	6

All the airlines are compared on the fleets page.

Neighbours in the ranking

Nearby airline results

These airlines sit nearby by passenger-miles per gallon in their last data year. Historical airlines have different end years, shown here, so this isn't a same-year ranking.

Airline references

• Wikipedia: Frontier Airlines
• Official site: Frontier Airlines

Source: US Bureau of Transportation Statistics (BTS), Schedule P-12(a) fuel, T-100 traffic and regional Schedule T-2 filings; US EPA jet-fuel CO2 factor. See the methodology.