United Airlines
Corporate Impact Report 2024

Environment

Environmental data including emissions, energy, water and waste

Greenhouse Gas Emissions

Direct (Scope 1) emissions

2024metric tons CO2e2023metric tons CO2e2022metric tons CO2e2021metric tons CO2e
Direct (Scope 1) emissions38,520,02736,588,996*30,400,71521,375,343
Mainline aircraft direct emissions38,388,47436,453,05630,263,43121,253,384
Conventional jet fuel38,387,48436,452,52830,263,21621,253,316
Sustainable aviation fuel - CH4 and N2O99052821568
Mainline vehicles (diesel, gasoline, CNG LPG)53,48952,97647,44738,242
Facilities (natural gas combustion, engine test cells)78,06482,96489,83781,997
Dry ice from catering0001,720

Biogenic emissions - outside of scopes

2024metric tons CO2e2023metric tons CO2e2022metric tons CO2e2021metric tons CO2e
Biogenic emissions - outside of scopes125,37468,871*26,8065,745
Mainline aircraft emissions - CO2 from sustainable aviation fuelFootnote 1125,37468,871*26,8065,745

Indirect (Scope 2) emissions

2024metric tons CO2e2023metric tons CO2e2022metric tons CO2e2021metric tons CO2e
Indirect (Scope 2) emissions (market-based)134,497144,019149,252160,794
Electricity consumption (location-based)160,201160,340166,757183,311
Electricity consumption (market-based)134,490143,991149,251160,794
Steam consumption72800

Other Indirect (Scope 3) emissions

2024metric tons CO2e2023metric tons CO2e2022metric tons CO2e2021metric tons CO2e
Other Indirect (Scope 3) emissions13,585,20712,671,51013,343,67612,170,494
Category 3 - Mainline aircraft fuel production7,821,3757,391,9367,250,1965,106,044
Conventional jet fuel7,796,4177,377,8147,246,4785,104,506
Sustainable aviation fuel24,95714,1223,7181,538
Category 4 - Regional aircraft direct emissions and fuel production5,317,6884,873,5625,587,3226,569,358
Regional aircraft and bus-operated flights flown under capacity purchase agreement - direct emissions4,383,1614,048,1834,504,6645,294,725
Regional vehicles (diesel, gasoline, CNG, LPG)12,50212,79914,53315,481
Regional aircraft flown under capacity purchase agreement - fuel production894,682789,1891,030,6881,202,863
Regional aircraft flown on an at-risk basis - fuel production27,34323,39137,43756,289
Category 7 - Employee commuting123,171125,795111,10852,278
Category 14 - Regional aircraft flown on an at-risk basis139,246122,425163,902243,553
Category 15 - Ownership stake in Azul Brazilian Airlines183,190156,432229,912199,099
Category 15 - United Airlines Ventures investmentsFootnote 25371,3611,236162

Gross emissions

2024metric tons CO2e2023metric tons CO2e2022metric tons CO2e2021metric tons CO2e
Gross GHG emissions (market-based)52,239,73149,404,525*43,893,64233,706,631
Carbon offsets0000
Net GHG emissions52,239,73149,404,525*43,893,64233,706,631

Carbon Emissions Intensity Rates

2024202320222021
United-specific metric tons CO2e per million RTKsFootnote 3 1,041.91,056.91,097.71,317.3
General-use customer metric tons CO2e per million RTKsFootnote 41,044.41,058.31,098.41,317.5
Revenue tonne-kilometers (RTKs – millions) 49,71146,36139,52625,212
United-specific metric tons CO2e per million ASMsFootnote 5 167.3169.0176.2187.5
General-use customer metric tons CO2e per million ASMsFootnote 6 167.7169.3176.2187.6
Available seat-miles (ASMs – millions) 311,185291,333247,858178,684

Energy consumption

2024202320222021
Conventional jet fuel - Mainline aircraft, in millions of gallons3,9773,7793,1392,205
Sustainable aviation fuel - Mainline aircraft, in millions of gallons13.67.32.90.6
Lifecycle reduction from SAF83.5%82.4%86.9%83.4%
Emissions reductions from SAF (metric tons CO2e)126,17411,3083,419987
Conventional jet fuel - Regional aircraft, in millions of gallons453418466523
Electricity (MWh)463,619434,790435,259447,714
Natural gas (MM BTUs)1,390,7941,481,6041,628,7221,494,698

Local air quality

Nitrogen Oxide emissions

2024tons2023tons2022tons2021tons
Total NOx emissions20,23311,55416,14411,626
Mainline aircraft (jet fuel)19,10610,35614,94810,813
Vehicles (diesel, gasoline, CNG, LPG)9731,1971,196813
Facilities (Natural gas combustion, engine test cells)154156153121

Sulfur Dioxide emissions

2024tons2023tons2022tons2021tons
Total SO2 emissions1,7701,2511,4141,022
Mainline aircraft (jet fuel)1,7691,2501,4131,022
Vehicles (diesel, gasoline, CNG, LPG)0000
Facilities (Natural gas combustion, engine test cells)1111

Carbon Monoxide emissions

2024tons2023tons2022tons2021tons
Total CO emissions13,47916,08916,75910,507
Mainline aircraft (jet fuel)9,8249,0277,8055,503
Vehicles (diesel, gasoline, CNG, LPG)3,5746,9778,8644,921
Facilities (Natural gas combustion, engine test cells)81859183

Waste management

2024metric tons2023metric tons2022metric tons2021metric tons
Waste-total79,75956,31725,17631,407
Hazardous and non-hazardous waste generation42,00219,30322,39924,253
Catering-Municipal waste37,75737,0142,77610,367
Recycling-total14,8399,2096,1125,818
Non-catering-recycled8,8825,0475,2554,446
Catering-recycled5,9574,1588571,372

Water consumption

2024millions of gallons2023millions of gallons2022millions of gallons2021millions of gallons
Billed water consumptionFootnote 7390429329661

The reporting period is January 1, 2024-December 31, 2024. The reporting boundary includes facilities and equipment under United Airline’s operational control. It excludes emissions from subsidiaries and joint ventures that are not operationally material. Our GHG Emissions Footprint is calculated using methodologies from the GHG Protocol and ISO14064-1.

CO2e emissions include carbon dioxide, methane and nitrous oxide emissions aggregated in accordance with the GHG Protocol using AR6 Global Warming Potentials (GWPs) and consist of the following:

  • Scope 1: Consists of direct GHG emissions generated by United’s operations including the combustion of conventional jet fuel and SAF by mainline and regional aircraft (TTW), fuel consumed by ground support equipment, and natural gas used in our facilities and airport spaces.
  • Scope 2: Consists of GHG emissions from the use of purchased electricity and steam used in our facilities and airport spaces.
  • Scope 3: Includes indirect GHG emissions from: Category 3, Fuel- and energy-related activities (WTT); Category 4, upstream transportation and distribution; Category 7, employee commuting; Category 14 franchises; and Category 15, investments.
  • Biogenic: CO2 emissions from the combustion of SAF which contains biologically sequestered carbon dioxide.
  • GHG emissions factors from: IATA, July 2023 release; The Climate Registry, February 2024 release; International Energy Agency, September 2024 release; The U.S. EPA GHG Emission Factors Hub and eGRID, January 2025 release.

The data presented herein reflecting United’s 2024 GHG emissions footprint has been internally validated by United Airlines Internal Audit Department and externally verified by our third-party verification party ERM. United obtains this third-party verification of our GHG emissions on an annual basis. ERM Certification and Verification Services (ERM CVS, a wholly owned subsidiary of the ERM Group, a global market leader in sustainability services) conducts our emissions verification and provides an ISO 14064-3 limited assurance on our GHG emissions for reporting.

Download our GHG Emissions Verification Report

Footnotes

  1. United accounts emissions reductions associated with the use and combustion of sustainable aviation fuel (SAF) to be a Scope 1 reduction, as it is in-sector and a sustainable alternative to the conventional jet fuel usage that is accounted in the gross emissions of this Scope.
  2. United Airlines Ventures investments include Alder Renewables, Archer Aviation, Boom, Electric Power Systems, EOS, Eve Air Mobility, Fulcrum BioEnergy, Heart Aerospace, Natron Energy and ZeroAvia, with most not yet operating at a stage that would produce material GHG emissions.
  3. Intensity metric used to track progress against United's near-term 2035 target. Includes Scope 1, Scope 2, and Scope 3 categories 3 and 4 emissions. This intensity figure considers all SAF for which United claimed Scope 1 emissions reductions from, including SAF for which specific customers or parties have retained Scope 3 end-user rights. This intensity should not be used for reporting purposes by general-use customers.
  4. General-use customer intensities consider only SAF for which United has claimed Scope 1 emissions reductions and maintained ownership of end-user attributes, enabling the use of this figure for reporting by United's general-use customers.
  5. Includes Scope 1, Scope 2, and Scope 3 categories 3, 4, 7 and 14 emissions. This intensity figure considers all SAF for which United claimed Scope 1 emissions reductions from, including SAF for which specific customers or parties have retained Scope 3 end-user rights. This intensity should not be used for reporting purposes by general-use customers.
  6. General-use customer intensities consider only SAF for which United has claimed Scope 1 emissions reductions and maintained ownership of end-user attributes, enabling the use of this figure for reporting by United's general-use customers.
  7. Does not account for all United locations or locations shared with other companies (e.g., airport terminals) and as a result may change considerably from year to year

* The calculation has been revised since the publication of United’s Form 10-K to incorporate additional SAF volumes for which supporting documentation was received after the initial filing.

Totals may not add up due to rounding.