Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Use of Estimates

Use of Estimates—The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("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.

Revenue Recognition

Revenue Recognition—Passenger revenue is recognized when transportation is provided and Cargo revenue is recognized when shipments arrive at their destination. Other operating revenue is recognized as the related performance obligations are satisfied.

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.

The Company estimates the value of Advance ticket sales that will expire unused ("breakage") and recognizes revenue and any changes in estimates in proportion to the usage of the related tickets. To determine 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.

In the years ended December 31, 2023, 2022 and 2021, the Company recognized approximately $5.7 billion, $3.3 billion and $1.8 billion, respectively, of passenger revenue for tickets that were included in Advance ticket sales at the beginning of those periods.

Revenue by Geography. The Company further disaggregates revenue by geographic regions. The Company deploys its aircraft across its route network through a single route scheduling system to maximize its value. When making resource allocation decisions, the Company's chief operating decision maker evaluates flight profitability data, which considers aircraft type and route economics. The Company's chief operating decision maker makes resource allocation decisions to maximize the Company's consolidated financial results. Operating segments are defined as components of an enterprise with separate financial information, which are evaluated regularly by the chief operating decision maker and are used in resource allocation and performance assessments. Managing the Company as one segment allows management the opportunity to maximize the value of its route network.

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 Fees. 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.

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 recorded on a net basis and, as a result, are excluded from revenue.

Frequent Flyer Accounting

Frequent Flyer Accounting—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 one to six 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.

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.

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 logit regression model to estimate the probability that an account will redeem its current miles balance. The Company reviews its breakage estimates annually based upon the latest available information. The Company's estimate of the expected breakage of miles requires management judgment and current and future 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. For the portion of the outstanding miles that we estimate will not be redeemed, we recognize the associated value proportionally as the remaining miles are redeemed.

Co-Brand Agreement. United has a contract (the "Co-Brand Agreement") to sell MileagePlus miles to 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 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 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. We also evaluate volumes on an annual basis, which may result in a change in the allocation of the estimated consideration from the Co-Brand Agreement on a prospective basis.

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.

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 short-term or long-term in the consolidated balance sheets based on the expected timing of return of the assets to the Company or payment to an outside party.

Restricted cash-current—The December 31, 2023 balance includes amounts to be used for the payment of principal, interest and fees on the $4.8 billion of senior secured notes and a secured term loan facility (the "MileagePlus Financing") secured by substantially all of the assets of Mileage Plus Holdings, LLC ("MPH"), a direct wholly-owned subsidiary of United.

Restricted cash-non-current—The December 31, 2023 balance primarily includes collateral associated with the MileagePlus Financing, collateral for letters of credit and collateral associated with facility leases and other insurance-related obligations.

Investments

Investments—Highly liquid investments with maturities of greater than three months to a 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 Miscellaneous, net in the consolidated statements of 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 an 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 consolidated statements of operations. See Note 8 of this report for additional information related to investments.

Compensation received in connection with purchase agreements

Compensation received in connection with purchase agreements—The Company accounts for compensation received from vendors as deferred credits that will generally be recognized as a reduction to the cost of the asset received in future periods.

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. Property under finance leases and the related obligation for future lease payments are recorded at an amount equal to the initial present value of those lease payments. 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 including those related to contractual damages related to delays in delivery. These credits are deferred until the aircraft and engines are delivered and then applied as a reduction to the cost of the related equipment.Depreciation and amortization of owned depreciable assets is based on the straight-line method over the assets' estimated useful lives. Leasehold improvements are amortized over the remaining term of the lease, including estimated facility renewal options when renewal is reasonably certain at key airports, or the estimated useful life of the related asset, whichever is less. Properties under finance leases are amortized using the straight-line method over the life of the lease or, in the case of certain aircraft, over their estimated useful lives, whichever is shorter. Amortization of finance lease assets 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 capacity purchase agreements ("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

Intangibles—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 reviewed for impairment on an annual basis as of October 1, or more frequently if events or circumstances indicate that the asset may be impaired. When there is a triggering event, 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. Because we are required to make estimates and assumptions when evaluating goodwill and indefinite-lived intangible assets for impairment, actual results may differ materially from these estimates. We recognize an impairment when the fair value of an intangible asset is less than its carrying value.

Every year, the Company evaluates its intangible assets for possible impairments. 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 inputs into the models included forecasted revenues, fuel costs, other operating costs, 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, 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 4 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 consolidated statements of operations.

Recently Issued Accounting Standards

Recently Issued Accounting Standards— In June 2022, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2022-03, Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions. Under this standard, a contractual restriction on the sale of an equity security is not considered in measuring the security's fair value. The standard also requires certain disclosures for equity securities that are subject to contractual sale restrictions. The ASU became effective January 1, 2024. We do not expect this ASU to have a material impact on the valuation of our equity investments; however, we may be required to include additional disclosures to the extent we have material equity investments subject to contractual sale restrictions.

Fair Value Information

Accounting standards require us to use 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

Assets and liabilities measured at fair value are based on the valuation techniques identified in the tables below. The valuation techniques are as follows:

(a) Market approach. Prices and other relevant information generated by market transactions involving identical or comparable assets and liabilities; and

(b) Income approach. Techniques to convert future amounts to a single current value based on market expectations (including present value techniques, option-pricing and excess earnings models).