Boeing 737-800

What the figures say

Boeing 737-800 ranks 8 of 25 types for seat-miles per gallon in 2025, at 79.1. Over 1,000 miles, one seat on this type accounts for about 123 kg of CO2 from the fuel burned.

US airlines burned 2,235 million gallons on the Boeing 737-800 in 2025, 11.9% of the fuel burned on all scheduled passenger flying, over 2,351 thousand airborne hours and 1,100 thousand departures. The average flight spent 2.1 hours in the air and burned 2,031 gallons.

Since 2001, when it was first flown in volume, the type's figure has risen from 67.9 to 79.1 seat-miles per gallon (16%). Its best year was 2020, at 87.0. The average flight got shorter, from 2.3 to 2.1 hours in the air, which tends to raise fuel burn per seat-mile, because take-off and climb take a larger share of the fuel on a short flight. Fuel per airborne hour fell 4.3%, from 994 to 951 gallons.

Airlines get different results from the same aircraft. Sun Country Airlines flew 94.0 seat-miles per gallon on it and Delta Air Lines 73.0, a gap of 29%. The seat count explains most of it: Sun Country Airlines put 186 seats on each flight against 160 at Delta Air Lines. Flight length differs too, at 2.8 hours in the air per flight for Sun Country Airlines and 2.2 for Delta Air Lines, and longer flights burn less fuel per seat-mile, which helps Sun Country Airlines. What's left comes from taxi and holding time, weight, engines, how each airline operates and how it allocates fuel to types when it reports, and the filings can't separate those.

What one seat costs the climate

CO2 for one seat on a Boeing 737-800, from the fuel burned, at the 2025 average.

• 62 kgover 500 miles
• 123 kgover 1,000 miles
• 247 kgover 2,000 miles

Who flies it, and how they burn

Boeing 737-800 by airline, 2025

Airline	Fuel (million gallons)	Gallons per airborne hour	Seats per flight	Hours per flight	Seat-miles per gallon
American Airlines	847	997	172	2.2	75.9
Southwest Airlines	595	896	175	1.9	85.2
United Airlines	337	965	166	2.2	76.3
Delta Air Lines	205	971	160	2.2	73.0
Alaska Airlines	158	902	159	2.8	80.4
Sun Country Airlines	67	901	186	2.8	94.0
Avelo Airlines	23	945	186	2.2	84.4

Seats on the Boeing 737-800, airline by airline

The Boeing 737-800 has 154 seats at United Airlines and 189 at Avelo Airlines, 23% more on the same model. The seat count is what each airline reports for its own aircraft in 2025, for airlines with 10 or more.

Boeing 737-800 fleets, 2025

Airline	Aircraft	Average seats	Fewest to most	Average age
United Airlines	141	154.0	154	21.5
Alaska Airlines	59	157.2	157 to 160	17.1
Delta Air Lines	77	160.0	160	23.9
American Airlines	303	172.0	172	15.6
Southwest Airlines	198	175.0	175	9.8
Sun Country Airlines	44	183.3	68 to 186	16.4
Avelo Airlines	14	189.0	189	15.5

See every airline's fleet on the fleets page.

Similar-sized aircraft

These types carry within about 25 seats of the Boeing 737-800, so they compete for the same routes.

More from Boeing

Browse the Boeing manufacturer hub and its other profiled types:

• Boeing 737 MAX 9
• Boeing 737 MAX 8
• Boeing 787-10
• Boeing 737-900ER
• Boeing 757-300
• Boeing 787-9
• Boeing 787-8
• Boeing 737-700
• Boeing 757-200
• Boeing 767-400ER
• Boeing 777-300ER
• Boeing 777-200
• Boeing 767-300ER

Nearby in fuel efficiency

Types on either side of this one in the seat-miles per gallon table, regardless of size:

Aircraft references

• Wikipedia: Boeing 737-800

Source: US Bureau of Transportation Statistics (BTS), Schedule T-2 fuel and airborne hours; US EPA jet-fuel CO2 factor. See the methodology and flight-hour definitions.

Back to all aircraft types, or see how the airlines compare on the airline pages.