BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
Dec. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation United Airlines Holdings, Inc. (together with its consolidated subsidiaries, "UAL" or the "Company") is a holding company incorporated in Delaware and its wholly-owned subsidiary is United Airlines, Inc. (together with its consolidated subsidiaries, "United"). As UAL consolidates United for financial statement purposes, disclosures that relate to activities of United also apply to UAL, unless otherwise noted. United comprises substantially all of UAL's operating revenues, operating expenses, assets, liabilities and operating cash flows. When appropriate, UAL and United are named specifically for their individual contractual obligations and related disclosures and any significant differences between the operations and results of UAL and United are separately disclosed and explained. The Company’s consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP"). The Company consolidates variable interest entities where it has been determined that the Company is the primary beneficiary of those entities' operations. All significant intercompany accounts and transactions have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform to the current period presentation.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these financial statements and accompanying notes. Actual results could differ from those estimates.
Segments	Segments Operating segments are defined as components of an enterprise with separate financial information, which are evaluated regularly by the chief operating decision maker ("CODM") and are used in resource allocation and performance assessments. The Company manages it operations as one segment. Managing the Company as one segment allows management the opportunity to maximize the value of its route network and maximize the Company's consolidated financial results. The Company deploys its aircraft across its route network through a single route scheduling system to maximize its value. The Company's chief executive officer is its CODM. When making resource allocation decisions for the network, the Company's CODM evaluates flight profitability data, which considers aircraft type and route economics. The CODM assesses performance of the Company and makes resource allocation decisions based on net income as reported in the Company's statement of consolidated operations. The measure of segment assets is reported on the consolidated balance sheet as Total assets. Within the statement of consolidated operations, Other expenses represent various purchased services related to the operations of the airline such as ground handling, passenger services, food and beverage offerings, navigation fees, personnel-related costs and information technology projects.
Cash and Cash Equivalents and Restricted Cash	Cash and Cash Equivalents and Restricted Cash. Highly liquid investments with a maturity of three months or less on their acquisition date are classified as cash and cash equivalents. Restricted cash is classified as current or noncurrent in the consolidated balance sheets based on the expected timing of return of the assets to the Company or payment to an outside party. The restricted cash balances primarily include collateral associated with the senior secured notes (the "MileagePlus Senior Secured Notes") secured by substantially all of the assets of Mileage Plus Holdings, LLC ("MPH"), a direct wholly-owned subsidiary of United, collateral for letters of credit and collateral associated with facility leases and certain insurance-related obligations.
Investments	Investments. Highly liquid investments with maturities of greater than three months, but not beyond one year, at the time of purchase are classified as short-term investments and are stated at fair value. Investments with maturities beyond one year when purchased are classified as short-term investments if they are expected to be available to support our short-term liquidity needs. Our short-term investments in debt securities are classified as available-for-sale and are stated at fair value. Realized gains and losses on sales of these investments are reflected in Interest income in the statements of consolidated operations. Unrealized gains and losses on available-for-sale debt securities are reflected as a component of accumulated other comprehensive income (loss). Equity investments are accounted for under the equity method if we are able to exercise significant influence over the investee. Equity investments for which we do not have significant influence are recorded at fair value or at cost, if fair value is not readily determinable, with adjustments for observable changes in price or impairments (referred to as the measurement alternative). Changes in fair value are recorded in Unrealized gains (losses) on investments, net in the statements of consolidated operations. See Note 9 of this report for additional information related to investments.
Accounts Receivable	Accounts Receivable. Accounts receivable primarily consist of amounts due from credit card companies, non-airline partners, and cargo customers. We provide an allowance for credit losses expected to be incurred. We base our allowance on various factors including, but not limited to, aging, payment history, write-offs, macro-economic indicators and other credit monitoring indicators.
Aircraft Fuel, Spare Parts and Supplies	Aircraft Fuel, Spare Parts and Supplies. The Company accounts for aircraft fuel, spare parts and supplies at average cost and provides an obsolescence allowance for aircraft spare parts with an assumed residual value of 10% of original cost.
Property and Equipment	Property and Equipment. The Company records additions to owned operating property and equipment at cost when acquired. Costs related to modifications that enhance the operating performance or extend the useful lives of airframes or engines are capitalized as property and equipment. We periodically receive credits in connection with the acquisition of aircraft and engines as well as contractual damages related to delays in delivery or operating performance issues. These credits are generally deferred and are recognized as a reduction to the cost of the related equipment. Depreciation and amortization is recognized on a straight-line basis over the assets' estimated useful lives. Leasehold improvements are amortized over the shorter of the remaining term of the lease or the estimated useful life of the related asset.
Leases	Leases. The Company enters into various leases as a lessee for assets including, but not limited to, airport facilities, airport gates, hanger sites, administrative offices, aircraft, and various other facilities and equipment to support its operations. The Company determines if an arrangement contains a lease at inception. A lease exists when the arrangement conveys the right to control the use of an identified asset over the lease term. Upon lease commencement, the Company records a lease liability for the obligation to make lease payments and right-of-use ("ROU") asset for the right to use the underlying asset for the lease term in the consolidated balance sheets. The lease liability is measured at the commencement date based on the present value of lease payments not yet paid over the lease term, which includes extension and renewal options that are reasonably certain of being exercised, discounted using an incremental borrowing rate that reflects the term of the lease and the particular economic environment at lease commencement. The ROU asset is based on the lease liability, adjusted for lease prepayments, lease incentives received, and the lessee's initial direct costs. The Company does not record a right-of-use asset or lease liability for leases with an initial term of 12 months or less. Lease and non-lease components are combined for all classes of underlying assets, except for capacity purchase agreements ("CPAs") which contain embedded leases for regional aircraft. For these CPAs, the Company allocates consideration to the lease and non-lease components based on their relative standalone values. Many of the Company's leases include variable lease payments, which are not included in the measurement of the right-of-use asset and lease liability. Finance lease right-of-use assets are presented together with Operating property and equipment on the consolidated balance sheets and the related amortization is included in Depreciation and amortization expense.
Long-Lived Asset Impairments	Long-Lived Asset Impairments. The Company evaluates the carrying value of long-lived assets subject to amortization whenever events or changes in circumstances indicate that an impairment may exist. For purposes of this testing, the Company has generally identified the aircraft fleet type as the lowest level of identifiable cash flows for its mainline fleet and the contract level for its regional fleet under CPAs. An impairment charge is recognized when the asset's carrying value exceeds its net undiscounted future cash flows. The amount of the charge is the difference between the asset's carrying value and fair market value.
Intangibles Assets	Intangible Assets. The Company has finite-lived and indefinite-lived intangible assets, including goodwill. Finite-lived intangible assets are amortized over their estimated useful lives. Goodwill and indefinite-lived intangible assets are not amortized but are assessed for impairment on an annual basis as of October 1, or more frequently if events or circumstances indicate that the asset may be impaired. The Company typically determines fair value using either market or a variation of the income approach valuation techniques. These measurements include the following key assumptions: (1) forecasted revenues, expenses, margin and cash flows, (2) terminal period growth rate, (3) an estimated weighted average cost of capital, (4) asset-specific risk factor and (5) a tax rate. These assumptions are consistent with those that hypothetical market participants would use. We recognize an impairment when the fair value of an intangible asset is less than its carrying value. For the Company's China route authority, the Company performed a quantitative assessment which involved determining the fair value of the asset and comparing that amount to the asset's carrying value. For all other intangible assets, the Company performed a qualitative assessment of whether it was more likely than not that an impairment had occurred. To determine fair value of the China route authority, the Company used a discounted cash flow method. Key assumptions used in the valuation model included forecasted revenues, margin and an overall discount rate. These assumptions are inherently uncertain as they relate to future events and circumstances.
Labor Costs	Labor Costs. The Company records expenses associated with new or amendable labor agreements when the amounts are probable and estimable. These could include costs associated with retro-active lump sum cash payments made in conjunction with the ratification of labor agreements. To the extent these upfront costs are in lieu of future pay increases, they would be capitalized and amortized over the term of the labor agreements. If not, these amounts would be expensed.
Share-Based Compensation	Share-Based Compensation. The Company measures the cost of employee services received in exchange for an award of equity instruments based on the grant date fair value of the award. The resulting cost is recognized over the period during which an employee is required to provide service in exchange for the award, which is usually the vesting period. Obligations for cash-settled restricted stock units ("RSUs") are remeasured at fair value throughout the requisite service period at the close of the reporting period based upon UAL's stock price. In addition to the service requirement, certain RSUs have performance metrics that must be achieved prior to vesting. These awards are accrued based on the expected level of achievement at each reporting period. An adjustment is recorded each reporting period to adjust compensation expense based on the then current level of expected performance achievement for the performance-based awards. See Note 5 of this report for additional information on UAL's share-based compensation plans.
Maintenance and Repairs	Maintenance and Repairs. The cost of maintenance and repairs, including the cost of minor replacements, is charged to expense as incurred, except for costs incurred under our power-by-the-hour ("PBTH") engine maintenance agreements. PBTH contracts transfer certain risk to third-party service providers and fix the amount we pay per flight hour or per cycle to the service provider in exchange for maintenance and repairs under a predefined maintenance program. Under PBTH agreements, the Company recognizes expense at a level rate per engine hour, unless the level of service effort and the related payments during the period are substantially consistent, in which case the Company recognizes expense based on the amounts paid.
Advertising	Advertising. Advertising costs, which are included in Other operating expenses, are expensed as incurred.
Third-Party Business	Third-Party Business. The Company has third-party business activity that includes ground handling, maintenance services, flight academy and frequent flyer award non-travel redemptions. Third-party business revenue is recorded in Other operating revenue. Expenses associated with these third-party business activities are recorded in Other operating expenses, except for non-travel mileage redemption. Non-travel mileage redemption expenses are recorded to Other operating revenue.
Uncertain Income Tax Positions	Uncertain Income Tax Positions. The Company has recorded reserves for income taxes and associated interest that may become payable in future years. Although management believes that its positions taken on income tax matters are reasonable, the Company nevertheless established tax and interest reserves in recognition that various taxing authorities may challenge certain of the positions taken by the Company, potentially resulting in additional liabilities for taxes and interest. The Company's uncertain tax position reserves are reviewed periodically and are adjusted as events occur that affect its estimates, such as the availability of new information, the lapsing of applicable statutes of limitation, the conclusion of tax audits, the measurement of additional estimated liability, the identification of new tax matters, the release of administrative tax guidance affecting its estimates of tax liabilities, or the rendering of relevant court decisions. The Company records penalties and interest relating to uncertain tax positions as part of income tax expense in its statements of consolidated operations.
Fair Value Measurements	Fair Value Measurements. The Company measures certain financial assets and liabilities at fair value on a recurring basis, and certain non-financial assets and liabilities on a nonrecurring basis. The Company uses valuation techniques to measure fair value that maximize the use of observable inputs and minimize the use of unobservable inputs. These inputs are prioritized as follows: •Level 1 - Unadjusted quoted prices in active markets for assets or liabilities identical to those to be reported at fair value •Level 2 - Other inputs that are observable directly or indirectly, such as quoted prices for similar assets or liabilities or market-corroborated inputs •Level 3 - Unobservable inputs for which there is little or no market data and which require us to develop our own assumptions about how market participants would price the assets or liabilities.
Recently Issued Accounting Standards	Recently Issued Accounting Standards Income Taxes. In December 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2023-09, "Income Taxes (Topic 740): Improvements to Income Tax Disclosures." This ASU enhances disclosures related to income taxes, including the rate reconciliation and information on income taxes paid. This ASU becomes effective for us on January 1, 2025. We are assessing the impact of this ASU and upon adoption may be required to include certain additional disclosures. Expense Disaggregation. In November 2024, the FASB issued ASU No. 2024-03, "Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses." This ASU requires disclosing disaggregated information about certain income statement expense captions but does not change the presentation of expense information or expense captions reported on the face of the income statement. This ASU is effective for annual reporting periods beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027; early adoption is permitted. We are assessing the impact of this ASU and upon adoption may be required to include certain additional disclosures.
Revenue Recognition	Passenger Revenue. Passenger revenue is recognized when transportation is provided. Passenger tickets and related ancillary services sold by the Company for flights are purchased primarily via credit card transactions, with payments collected by the Company in advance of the performance of related services. The Company initially records ticket sales in its Advance ticket sales liability, deferring revenue recognition until the travel occurs. For travel that has more than one flight segment, the Company deems each segment as a separate performance obligation and recognizes revenue for each segment as travel occurs. Tickets sold by other airlines where the Company provides the transportation are recognized as passenger revenue at the estimated value to be billed to the other airline when travel is provided. Differences between amounts billed and the actual amounts may be rejected and rebilled or written off if the amount recorded was different from the original estimate. When necessary, the Company records a reserve against its billings and payables with other airlines based on historical experience. The Company sells certain tickets with connecting flights with one or more segments operated by its other airline partners. For segments operated by its other airline partners, the Company has determined that it is acting as an agent on behalf of the other airlines as they are responsible for their portion of the contract (i.e. transportation of the passenger). The Company, as the agent, recognizes revenue within Other operating revenue at the time of the travel for the net amount representing commission to be retained by the Company for any segments flown by other airlines. Refundable tickets expire after one year from the date of issuance. Non-refundable tickets generally expire on the date of the intended travel, unless the date is extended by notification from the customer on or before the intended travel date. United initially capitalizes the costs of selling airline travel tickets and then recognizes those costs as Distribution expense at the time of travel. Costs to sell a ticket include credit card fees, travel agency and other commissions paid, as well as global distribution systems booking fees. Advance ticket sales. Advance ticket sales represent the Company's liability to provide air transportation in the future. All tickets sold at any given point in time have travel dates through the next 12 months. The Company defers amounts related to future travel in its Advance ticket sales liability account. Estimate of tickets not expected to be used ("ticket breakage"). The Company estimates the value of Advance ticket sales that will expire unused and recognizes revenue and any changes in estimates in proportion to the usage of the related tickets. To determine ticket breakage, the Company uses its historical experience with expired tickets and certificates and other facts, such as recent aging trends, program changes and modifications that could affect the ultimate expiration patterns. The Company attributes revenue among the geographic areas based upon the origin and destination of each flight segment. The Company's operations involve an insignificant level of revenue-producing assets in geographic regions as the overwhelming majority of the Company's revenue-producing assets (primarily U.S. registered aircraft) can be deployed in any of its geographic regions. Ancillary services. The Company charges fees, separately from ticket sales, for certain ancillary services that are directly related to passengers' travel, such as baggage fees, premium seat fees, inflight amenity fees, and other ticket-related fees. These ancillary fees are part of the travel performance obligation and, as such, are recognized as passenger revenue when the travel occurs.Cargo Revenue. Cargo revenue is recognized when shipments arrive at their destination.
Ticket Taxes	Ticket Taxes. Certain governmental taxes are imposed on the Company's ticket sales through a fee included in ticket prices. The Company collects these fees and remits them to the appropriate government agency. These fees are excluded from the contract transaction price and are therefore not included in passenger revenue. We record a liability when amounts are collected and reduce the liability when payments are made to the appropriate taxing authority.
Frequent Flyer Accounting	Frequent Flyer Program. United's MileagePlus loyalty program builds customer loyalty by offering awards, benefits and services to program participants. Members in this program earn miles for travel on United, United Express, Star Alliance members and certain other airlines that participate in the program. Members can also earn miles by purchasing goods and services from our network of non-airline partners. We have contracts to sell miles to these partners with the terms extending from approximately one to five years. These partners include domestic and international credit card issuers, retail merchants, hotels, car rental companies and our participating airline partners. Miles can be redeemed for free (other than taxes and government-imposed fees), discounted or upgraded air travel and non-travel awards. Miles earned in conjunction with travel. When frequent flyers earn miles for flights, the Company recognizes a portion of the ticket sales as revenue when the travel occurs and defers a portion of the ticket sale representing the value of the related miles as a separate performance obligation. The Company determines the estimated selling price of travel and miles as if each element is sold on a separate basis. The total consideration from each ticket sale is then allocated to each of these elements, individually, on a pro-rata basis. At the time of travel, the Company records the portion allocated to the miles to Frequent flyer deferred revenue on the Company's consolidated balance sheet and subsequently recognizes it into revenue when miles are redeemed for air travel and non-air travel awards. Estimate of miles not expected to be redeemed ("breakage"). The Company's breakage model is based on the assumption that the likelihood that an account will redeem its miles can be estimated based on a consideration of the account's historical behavior. The Company uses a statistical model to estimate the probability that an account will redeem its current miles balance and reviews its breakage estimates annually. The Company's estimate of the expected breakage of miles requires management judgment. Changes to breakage assumptions, or to program rules and program redemption opportunities, may result in material changes to the deferred revenue balance as well as recognized revenues from the program. We recognize breakage proportionally as the remaining miles are redeemed. Estimated selling price of miles. The Company's estimated selling price of miles is based on an equivalent ticket value, which incorporates the expected redemption of miles, as the best estimate of selling price for these miles. The equivalent ticket value is based on the prior 12 months' weighted average equivalent ticket value of similar fares as those used to settle award redemptions while taking into consideration such factors as redemption pattern, cabin class, loyalty status and geographic region. The estimated selling price of miles is adjusted by breakage that considers a number of factors, including redemption patterns of various customer groups. Co-Brand agreement. United's most significant contract to sell MileagePlus miles is with its co-branded credit card partner JPMorgan Chase Bank USA, N.A. ("Chase"). Chase awards miles to MileagePlus members based on their credit card activity. United identified the following significant separately identifiable performance obligations in this contract (the "Co-Brand Agreement"): •MileagePlus miles awarded – United has a performance obligation to provide MileagePlus cardholders with miles to be used for air travel and non-travel award redemptions. The Company records Passenger revenue related to the travel awards when the transportation is provided and records Other operating revenue related to the non-travel awards when the goods or services are delivered. The Company records the cost associated with non-travel awards in Other operating revenue, as an agent. •Marketing – United has a performance obligation to provide Chase access to United's customer list and the use of United's brand. Marketing revenue is recorded to Other operating revenue as miles are delivered to Chase. •Advertising – United has a performance obligation to provide advertising in support of the MileagePlus card in various customer contact points such as United's website, email promotions, direct mail campaigns, airport advertising and in-flight advertising. Advertising revenue is recorded to Other operating revenue as miles are delivered to Chase. •Other travel-related benefits – United's performance obligations are comprised of various items such as waived bag fees, seat upgrades and lounge passes. Lounge passes are recorded to Other operating revenue as customers use the lounge passes. Bag fees and seat upgrades are recorded to Passenger revenue at the time of the associated travel. We account for all the payments received under the Co-Brand Agreement by allocating them to the separately identifiable performance obligations. The fair value of the separately identifiable performance obligations is determined using management's estimated selling price of each component. The objective of using the estimated selling price based methodology is to determine the price at which we would transact a sale if the product or service were sold on a stand-alone basis. Accordingly, we determine our best estimate of selling price by considering multiple inputs and methods including, but not limited to, discounted cash flows, brand value, volume discounts, published selling prices, number of miles awarded and number of miles redeemed. The Company estimated the selling prices and volumes over the term of the Co-Brand Agreement, at the inception of the contract, in order to determine the allocation of proceeds to each of the components to be delivered. Frequent flyer deferred revenue. Miles in MileagePlus members' accounts are combined into one homogeneous pool and are thus not separately identifiable, for award redemption purposes, between miles earned in the current period and those in their beginning balance. Of the miles expected to be redeemed, the Company expects the majority of these miles to be redeemed within two years. The current portion of the Frequent flyer deferred revenue is based on expected redemptions in the next 12 months.

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Policies)

12 Months Ended

Dec. 31, 2024

United Airlines Holdings, Inc. (together with its consolidated subsidiaries, "UAL" or the "Company") is a holding company incorporated in Delaware and its wholly-owned subsidiary is United Airlines, Inc. (together with its consolidated subsidiaries, "United"). As UAL consolidates United for financial statement purposes, disclosures that relate to activities of United also apply to UAL, unless otherwise noted. United comprises substantially all of UAL's operating revenues, operating expenses, assets, liabilities and operating cash flows. When appropriate, UAL and United are named specifically for their individual contractual obligations and related disclosures and any significant differences between the operations and results of UAL and United are separately disclosed and explained.

The Company’s consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP"). The Company consolidates variable interest entities where it has been determined that the Company is the primary beneficiary of those entities' operations. All significant intercompany accounts and transactions have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform to the current period presentation.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these financial statements and accompanying notes. Actual results could differ from those estimates.

Segments

Operating segments are defined as components of an enterprise with separate financial information, which are evaluated regularly by the chief operating decision maker ("CODM") and are used in resource allocation and performance assessments. The Company manages it operations as one segment. Managing the Company as one segment allows management the opportunity to maximize the value of its route network and maximize the Company's consolidated financial results. The Company deploys its aircraft across its route network through a single route scheduling system to maximize its value. The Company's chief executive officer is its CODM. When making resource allocation decisions for the network, the Company's CODM evaluates flight profitability data, which considers aircraft type and route economics. The CODM assesses performance of the Company and makes resource allocation decisions based on net income as reported in the Company's statement of consolidated operations. The measure of segment assets is reported on the consolidated balance sheet as Total assets. Within the statement of consolidated operations, Other expenses represent various purchased services related to the operations of the airline such as ground handling, passenger services, food and beverage offerings, navigation fees, personnel-related costs and information technology projects.

Cash and Cash Equivalents and Restricted Cash

Cash and Cash Equivalents and Restricted Cash. Highly liquid investments with a maturity of three months or less on their acquisition date are classified as cash and cash equivalents. Restricted cash is classified as current or noncurrent in the consolidated balance sheets based on the expected timing of return of the assets to the Company or payment to an outside party. The restricted cash balances primarily include collateral associated with the senior secured notes (the "MileagePlus Senior Secured Notes") secured by substantially all of the assets of Mileage Plus Holdings, LLC ("MPH"), a direct wholly-owned subsidiary of United, collateral for letters of credit and collateral associated with facility leases and certain insurance-related obligations.

Investments

Investments. Highly liquid investments with maturities of greater than three months, but not beyond one year, at the time of purchase are classified as short-term investments and are stated at fair value. Investments with maturities beyond one year when purchased are classified as short-term investments if they are expected to be available to support our short-term liquidity needs. Our short-term investments in debt securities are classified as available-for-sale and are stated at fair value. Realized gains and losses on sales of these investments are reflected in Interest income in the statements of consolidated operations. Unrealized gains and losses on available-for-sale debt securities are reflected as a component of accumulated other comprehensive income (loss). Equity investments are accounted for under the equity method if we are able to exercise significant influence over the investee. Equity investments for which we do not have significant influence are recorded at fair value or at cost, if fair value is not readily determinable, with adjustments for observable changes in price or impairments (referred to as the measurement alternative). Changes in fair value are recorded in Unrealized gains (losses) on investments, net in the statements of consolidated operations. See Note 9 of this report for additional information related to investments.

Accounts Receivable

Accounts Receivable. Accounts receivable primarily consist of amounts due from credit card companies, non-airline partners, and cargo customers. We provide an allowance for credit losses expected to be incurred. We base our allowance on various factors including, but not limited to, aging, payment history, write-offs, macro-economic indicators and other credit monitoring indicators.

Aircraft Fuel, Spare Parts and Supplies

Aircraft Fuel, Spare Parts and Supplies. The Company accounts for aircraft fuel, spare parts and supplies at average cost and provides an obsolescence allowance for aircraft spare parts with an assumed residual value of 10% of original cost.

Property and Equipment

Property and Equipment. The Company records additions to owned operating property and equipment at cost when acquired. Costs related to modifications that enhance the operating performance or extend the useful lives of airframes or engines are capitalized as property and equipment. We periodically receive credits in connection with the acquisition of aircraft and engines as well as contractual damages related to delays in delivery or operating performance issues. These credits are generally deferred and are recognized as a reduction to the cost of the related equipment.

Depreciation and amortization is recognized on a straight-line basis over the assets' estimated useful lives. Leasehold improvements are amortized over the shorter of the remaining term of the lease or the estimated useful life of the related asset.

Leases

Leases. The Company enters into various leases as a lessee for assets including, but not limited to, airport facilities, airport gates, hanger sites, administrative offices, aircraft, and various other facilities and equipment to support its operations. The Company determines if an arrangement contains a lease at inception. A lease exists when the arrangement conveys the right to control the use of an identified asset over the lease term. Upon lease commencement, the Company records a lease liability for the obligation to make lease payments and right-of-use ("ROU") asset for the right to use the underlying asset for the lease term in the consolidated balance sheets. The lease liability is measured at the commencement date based on the present value of lease payments not yet paid over the lease term, which includes extension and renewal options that are reasonably certain of being exercised, discounted using an incremental borrowing rate that reflects the term of the lease and the particular economic environment at lease commencement. The ROU asset is based on the lease liability, adjusted for lease prepayments, lease incentives received, and the lessee's initial direct costs. The Company does not record a right-of-use asset or lease liability for leases with an initial term of 12 months or less. Lease and non-lease components are combined for all classes of underlying assets, except for capacity purchase agreements ("CPAs") which contain embedded leases for regional aircraft. For these CPAs, the Company allocates consideration to the lease and non-lease components based on their relative standalone values. Many of the Company's leases include variable lease payments, which are not included in the measurement of the right-of-use asset and lease liability. Finance lease right-of-use assets are presented together with Operating property and equipment on the consolidated balance sheets and the related amortization is included in Depreciation and amortization expense.

Long-Lived Asset Impairments

Long-Lived Asset Impairments. The Company evaluates the carrying value of long-lived assets subject to amortization whenever events or changes in circumstances indicate that an impairment may exist. For purposes of this testing, the Company has generally identified the aircraft fleet type as the lowest level of identifiable cash flows for its mainline fleet and the contract level for its regional fleet under CPAs. An impairment charge is recognized when the asset's carrying value exceeds its net undiscounted future cash flows. The amount of the charge is the difference between the asset's carrying value and fair market value.

Intangibles Assets

Intangible Assets. The Company has finite-lived and indefinite-lived intangible assets, including goodwill. Finite-lived intangible assets are amortized over their estimated useful lives. Goodwill and indefinite-lived intangible assets are not amortized but are assessed for impairment on an annual basis as of October 1, or more frequently if events or circumstances indicate that the asset may be impaired. The Company typically determines fair value using either market or a variation of the income approach valuation techniques. These measurements include the following key assumptions: (1) forecasted revenues, expenses, margin and cash flows, (2) terminal period growth rate, (3) an estimated weighted average cost of capital, (4) asset-specific risk factor and (5) a tax rate. These assumptions are consistent with those that hypothetical market participants would use. We recognize an impairment when the fair value of an intangible asset is less than its carrying value.

For the Company's China route authority, the Company performed a quantitative assessment which involved determining the fair value of the asset and comparing that amount to the asset's carrying value. For all other intangible assets, the Company performed a qualitative assessment of whether it was more likely than not that an impairment had occurred. To determine fair value of the China route authority, the Company used a discounted cash flow method. Key assumptions used in the valuation model included forecasted revenues, margin and an overall discount rate. These assumptions are inherently uncertain as they relate to future events and circumstances.

Labor Costs

Labor Costs. The Company records expenses associated with new or amendable labor agreements when the amounts are probable and estimable. These could include costs associated with retro-active lump sum cash payments made in conjunction with the ratification of labor agreements. To the extent these upfront costs are in lieu of future pay increases, they would be capitalized and amortized over the term of the labor agreements. If not, these amounts would be expensed.

Share-Based Compensation

Share-Based Compensation. The Company measures the cost of employee services received in exchange for an award of equity instruments based on the grant date fair value of the award. The resulting cost is recognized over the period during which an employee is required to provide service in exchange for the award, which is usually the vesting period. Obligations for cash-settled restricted stock units ("RSUs") are remeasured at fair value throughout the requisite service period at the close of the reporting period based upon UAL's stock price. In addition to the service requirement, certain RSUs have performance metrics that must be achieved prior to vesting. These awards are accrued based on the expected level of achievement at each reporting period. An adjustment is recorded each reporting period to adjust compensation expense based on the then current level of expected performance achievement for the performance-based awards. See Note 5 of this report for additional information on UAL's share-based compensation plans.

Maintenance and Repairs

Maintenance and Repairs. The cost of maintenance and repairs, including the cost of minor replacements, is charged to expense as incurred, except for costs incurred under our power-by-the-hour ("PBTH") engine maintenance agreements. PBTH contracts transfer certain risk to third-party service providers and fix the amount we pay per flight hour or per cycle to the service provider in exchange for maintenance and repairs under a predefined maintenance program. Under PBTH agreements, the Company recognizes expense at a level rate per engine hour, unless the level of service effort and the related payments during the period are substantially consistent, in which case the Company recognizes expense based on the amounts paid.

Advertising

Advertising. Advertising costs, which are included in Other operating expenses, are expensed as incurred.

Third-Party Business

Third-Party Business. The Company has third-party business activity that includes ground handling, maintenance services, flight academy and frequent flyer award non-travel redemptions. Third-party business revenue is recorded in Other operating revenue. Expenses associated with these third-party business activities are recorded in Other operating expenses, except for non-travel mileage redemption. Non-travel mileage redemption expenses are recorded to Other operating revenue.

Uncertain Income Tax Positions

Uncertain Income Tax Positions. The Company has recorded reserves for income taxes and associated interest that may become payable in future years. Although management believes that its positions taken on income tax matters are reasonable, the Company nevertheless established tax and interest reserves in recognition that various taxing authorities may challenge certain of the positions taken by the Company, potentially resulting in additional liabilities for taxes and interest. The Company's uncertain tax position reserves are reviewed periodically and are adjusted as events occur that affect its estimates, such as the

availability of new information, the lapsing of applicable statutes of limitation, the conclusion of tax audits, the measurement of additional estimated liability, the identification of new tax matters, the release of administrative tax guidance affecting its estimates of tax liabilities, or the rendering of relevant court decisions. The Company records penalties and interest relating to uncertain tax positions as part of income tax expense in its statements of consolidated operations.

Fair Value Measurements

Fair Value Measurements. The Company measures certain financial assets and liabilities at fair value on a recurring basis, and certain non-financial assets and liabilities on a nonrecurring basis. The Company uses valuation techniques to measure fair value that maximize the use of observable inputs and minimize the use of unobservable inputs. These inputs are prioritized as follows:

•Level 1 - Unadjusted quoted prices in active markets for assets or liabilities identical to those to be reported at fair value

•Level 2 - Other inputs that are observable directly or indirectly, such as quoted prices for similar assets or liabilities or market-corroborated inputs

•Level 3 - Unobservable inputs for which there is little or no market data and which require us to develop our own assumptions about how market participants would price the assets or liabilities.

Recently Issued Accounting Standards

Income Taxes. In December 2023, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2023-09, "Income Taxes (Topic 740): Improvements to Income Tax Disclosures." This ASU enhances disclosures related to income taxes, including the rate reconciliation and information on income taxes paid. This ASU becomes effective for us on January 1, 2025. We are assessing the impact of this ASU and upon adoption may be required to include certain additional disclosures.

Expense Disaggregation. In November 2024, the FASB issued ASU No. 2024-03, "Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses." This ASU requires disclosing disaggregated information about certain income statement expense captions but does not change the presentation of expense information or expense captions reported on the face of the income statement. This ASU is effective for annual reporting periods beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027; early adoption is permitted. We are assessing the impact of this ASU and upon adoption may be required to include certain additional disclosures.

Revenue Recognition

Passenger Revenue. Passenger revenue is recognized when transportation is provided.

Passenger tickets and related ancillary services sold by the Company for flights are purchased primarily via credit card transactions, with payments collected by the Company in advance of the performance of related services. The Company initially records ticket sales in its Advance ticket sales liability, deferring revenue recognition until the travel occurs. For travel that has more than one flight segment, the Company deems each segment as a separate performance obligation and recognizes revenue for each segment as travel occurs. Tickets sold by other airlines where the Company provides the transportation are recognized as passenger revenue at the estimated value to be billed to the other airline when travel is provided. Differences between amounts billed and the actual amounts may be rejected and rebilled or written off if the amount recorded was different from the original estimate. When necessary, the Company records a reserve against its billings and payables with other airlines based on historical experience.

The Company sells certain tickets with connecting flights with one or more segments operated by its other airline partners. For segments operated by its other airline partners, the Company has determined that it is acting as an agent on behalf of the other airlines as they are responsible for their portion of the contract (i.e. transportation of the passenger). The Company, as the agent, recognizes revenue within Other operating revenue at the time of the travel for the net amount representing commission to be retained by the Company for any segments flown by other airlines.

Refundable tickets expire after one year from the date of issuance. Non-refundable tickets generally expire on the date of the intended travel, unless the date is extended by notification from the customer on or before the intended travel date.

United initially capitalizes the costs of selling airline travel tickets and then recognizes those costs as Distribution expense at the time of travel. Costs to sell a ticket include credit card fees, travel agency and other commissions paid, as well as global distribution systems booking fees.

Advance ticket sales. Advance ticket sales represent the Company's liability to provide air transportation in the future. All tickets sold at any given point in time have travel dates through the next 12 months. The Company defers amounts related to future travel in its Advance ticket sales liability account.

Estimate of tickets not expected to be used ("ticket breakage"). The Company estimates the value of Advance ticket sales that will expire unused and recognizes revenue and any changes in estimates in proportion to the usage of the related tickets. To determine ticket breakage, the Company uses its historical experience with expired tickets and certificates and other facts, such as recent aging trends, program changes and modifications that could affect the ultimate expiration patterns.

The Company attributes revenue among the geographic areas based upon the origin and destination of each flight segment. The Company's operations involve an insignificant level of revenue-producing assets in geographic regions as the overwhelming majority of the Company's revenue-producing assets (primarily U.S. registered aircraft) can be deployed in any of its geographic regions.

Ancillary services. The Company charges fees, separately from ticket sales, for certain ancillary services that are directly related to passengers' travel, such as baggage fees, premium seat fees, inflight amenity fees, and other ticket-related fees. These ancillary fees are part of the travel performance obligation and, as such, are recognized as passenger revenue when the travel occurs.Cargo Revenue. Cargo revenue is recognized when shipments arrive at their destination.

Ticket Taxes

Ticket Taxes. Certain governmental taxes are imposed on the Company's ticket sales through a fee included in ticket prices. The Company collects these fees and remits them to the appropriate government agency. These fees are excluded from the contract transaction price and are therefore not included in passenger revenue. We record a liability when amounts are collected and reduce the liability when payments are made to the appropriate taxing authority.

Frequent Flyer Accounting

Frequent Flyer Program. United's MileagePlus loyalty program builds customer loyalty by offering awards, benefits and services to program participants. Members in this program earn miles for travel on United, United Express, Star Alliance members and certain other airlines that participate in the program. Members can also earn miles by purchasing goods and services from our network of non-airline partners. We have contracts to sell miles to these partners with the terms extending from approximately one to five years. These partners include domestic and international credit card issuers, retail merchants, hotels, car rental companies and our participating airline partners. Miles can be redeemed for free (other than taxes and government-imposed fees), discounted or upgraded air travel and non-travel awards.

Miles earned in conjunction with travel. When frequent flyers earn miles for flights, the Company recognizes a portion of the ticket sales as revenue when the travel occurs and defers a portion of the ticket sale representing the value of the related miles as a separate performance obligation. The Company determines the estimated selling price of travel and miles as if each element is sold on a separate basis. The total consideration from each ticket sale is then allocated to each of these elements, individually, on a pro-rata basis. At the time of travel, the Company records the portion allocated to the miles to Frequent flyer deferred revenue on the Company's consolidated balance sheet and subsequently recognizes it into revenue when miles are redeemed for air travel and non-air travel awards.

Estimate of miles not expected to be redeemed ("breakage"). The Company's breakage model is based on the assumption that the likelihood that an account will redeem its miles can be estimated based on a consideration of the account's historical behavior. The Company uses a statistical model to estimate the probability that an account will redeem its current miles balance and reviews its breakage estimates annually. The Company's estimate of the expected breakage of miles requires management judgment. Changes to breakage assumptions, or to program rules and program redemption opportunities, may result in material

changes to the deferred revenue balance as well as recognized revenues from the program. We recognize breakage proportionally as the remaining miles are redeemed.

Estimated selling price of miles. The Company's estimated selling price of miles is based on an equivalent ticket value, which incorporates the expected redemption of miles, as the best estimate of selling price for these miles. The equivalent ticket value is based on the prior 12 months' weighted average equivalent ticket value of similar fares as those used to settle award redemptions while taking into consideration such factors as redemption pattern, cabin class, loyalty status and geographic region. The estimated selling price of miles is adjusted by breakage that considers a number of factors, including redemption patterns of various customer groups.

Co-Brand agreement. United's most significant contract to sell MileagePlus miles is with its co-branded credit card partner JPMorgan Chase Bank USA, N.A. ("Chase"). Chase awards miles to MileagePlus members based on their credit card activity. United identified the following significant separately identifiable performance obligations in this contract (the "Co-Brand Agreement"):

•MileagePlus miles awarded – United has a performance obligation to provide MileagePlus cardholders with miles to be used for air travel and non-travel award redemptions. The Company records Passenger revenue related to the travel awards when the transportation is provided and records Other operating revenue related to the non-travel awards when the goods or services are delivered. The Company records the cost associated with non-travel awards in Other operating revenue, as an agent.

•Marketing – United has a performance obligation to provide Chase access to United's customer list and the use of United's brand. Marketing revenue is recorded to Other operating revenue as miles are delivered to Chase.

•Advertising – United has a performance obligation to provide advertising in support of the MileagePlus card in various customer contact points such as United's website, email promotions, direct mail campaigns, airport advertising and in-flight advertising. Advertising revenue is recorded to Other operating revenue as miles are delivered to Chase.

•Other travel-related benefits – United's performance obligations are comprised of various items such as waived bag fees, seat upgrades and lounge passes. Lounge passes are recorded to Other operating revenue as customers use the lounge passes. Bag fees and seat upgrades are recorded to Passenger revenue at the time of the associated travel.

We account for all the payments received under the Co-Brand Agreement by allocating them to the separately identifiable performance obligations. The fair value of the separately identifiable performance obligations is determined using management's estimated selling price of each component. The objective of using the estimated selling price based methodology is to determine the price at which we would transact a sale if the product or service were sold on a stand-alone basis. Accordingly, we determine our best estimate of selling price by considering multiple inputs and methods including, but not limited to, discounted cash flows, brand value, volume discounts, published selling prices, number of miles awarded and number of miles redeemed. The Company estimated the selling prices and volumes over the term of the Co-Brand Agreement, at the inception of the contract, in order to determine the allocation of proceeds to each of the components to be delivered.

Frequent flyer deferred revenue. Miles in MileagePlus members' accounts are combined into one homogeneous pool and are thus not separately identifiable, for award redemption purposes, between miles earned in the current period and those in their beginning balance. Of the miles expected to be redeemed, the Company expects the majority of these miles to be redeemed within two years. The current portion of the Frequent flyer deferred revenue is based on expected redemptions in the next 12 months.