Basis of Presentation and Summary of Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2023
Accounting Policies [Abstract]
Business Combination	Xos, Inc. was initially incorporated on July 29, 2020 as a Cayman Islands exempted company under the name “NextGen Acquisition Corporation” (“NextGen”). On August 20, 2021, the transactions contemplated by the Agreement and Plan of Merger, as amended on May 14, 2021, by and among NextGen, Sky Merger Sub I, Inc., a Delaware corporation and a direct wholly owned subsidiary of NextGen (“Merger Sub”), and Xos, Inc., a Delaware corporation (now known as Xos Fleet, Inc., “Legacy Xos”), were consummated (the “Closing”), whereby Merger Sub merged with and into Legacy Xos, the separate corporate existence of Merger Sub ceased and Legacy Xos became the surviving corporation and a wholly owned subsidiary of NextGen (such transaction the “Merger” and, collectively with the Domestication, the “Business Combination”). As a result, Xos became the publicly traded entity listed on the Nasdaq Global Market.
Basis of Presentation	The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and the rules and regulations of the Securities and Exchange Commission (the “SEC”) for interim financial information. They do not include all of the information and footnotes required by U.S. GAAP for complete audited financial statements. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Legacy Xos and Xos Services. All significant intercompany accounts and transactions have been eliminated in consolidation. In the opinion of management, all adjustments (primarily consisting of normal accruals) considered for a fair presentation have been included. Operating results for the three months ended March 31, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements as of and for the years ended December 31, 2022 and 2021 presented in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022 filed with the SEC on March 31, 2023.
Use of Estimates	The preparation of financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the balance sheet date, as well as reported amounts of revenues and expenses during the reporting periods. The areas with significant estimates and judgments include, among others, inventory valuation, incremental borrowing rates for assessing operating and financing lease liabilities, useful lives of property and equipment, contingent earn-out shares liability, stock-based compensation, valuation of convertible debt and related embedded derivatives, common stock warrant liability and product warranty liability. Management bases its estimates on historical experience and on various other assumptions believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results could differ from those estimates, and such differences could be material to the Company’s financial statements.
Accounts Receivable, Net	The Company records unsecured and non-interest bearing accounts receivable at the gross invoice amount, net of any allowance for expected credit losses. The Company maintains its allowance for expected credit losses at a level considered adequate to provide for potential account losses on the balance based on management’s evaluation of past losses, current customer conditions, and the anticipated impact of current economic conditions. The Company recorded an allowance for expected credit losses of $39,000 as of March 31, 2023. No allowance for doubtful accounts was recorded as of March 31, 2022.
Investments in Marketable Debt Securities, Available-for-Sale	The Company maintains a portfolio of investments in a variety of fixed and variable rate debt securities, including U.S. treasuries, corporate debt, asset-backed securities and other, non-U.S. government and supranational bonds and certificate of deposit. The Company considers its investments in marketable debt securities to be available-for-sale, and accordingly, are recorded at their fair values. The Company determines the appropriate classification of investments in marketable debt securities at the time of purchase. Unrealized gains and losses on marketable debt securities, available-for-sale are recorded in Accumulated other comprehensive loss which is included within stockholders’ equity. Interest along with amortization of purchase premiums and accretion of discounts from the purchase date through the estimated maturity date, including consideration of variable maturities and contractual call provisions, are included in other income (expenses), net in the condensed consolidated statements of operations and comprehensive loss. Realized gains and losses on the sale of marketable debt securities, available-for-sale are recorded in Other (expense) income, net. The Company typically invests in highly-rated debt securities, and its investment policy generally limits the amount of credit exposure to any one issuer. The policy requires substantially all investments to be investment grade, with the primary objective of minimizing the potential risk of principal loss. See Note 8 — Investments for additional information.On January 1, 2023, the Company adopted ASU 2016-13, Financial Instruments — Credit Losses which requires that credit losses be presented as an allowance rather than as an impairment write-down. Adoption of the standard had no material impact on its financial statements.The Company reviews quarterly its investment portfolio of all securities in an unrealized loss position to determine if an impairment charge or credit reserve is required. The Company excludes accrued interest from both the fair value and the amortized cost basis of marketable debt securities, available-for-sale, for the purposes of identifying and measuring an impairment. An investment is impaired if the fair value is less than its amortized cost basis. Impairment relating to credit losses is recorded through a reduction in the amortized cost of the security or an allowance for credit losses and credit loss expense (included in selling, general and administrative expense), limited by the amount that the fair value is less than the amortized cost basis. Impairment that has not been recorded as a credit loss is recorded through other comprehensive income (loss), net of applicable taxes. The Company made an accounting policy election to not measure an allowance for credit losses for accrued interest receivables. The Company evaluates write-off of accrued interest receivable at the time credit loss exists for the underlying security. As of March 31, 2023 and 2022, we did not recognize any allowance for expected credit losses or impairment, respectively, on marketable debt securities - available-for-sale.
Warranty Liability	The Company provides customers with a product warranty that assures that the products meet standard specifications and are free for periods typically between 2 to 5 years. The Company accrues warranty reserve for the products sold, which includes its best estimate of the projected costs to repair or replace items under warranties and recalls if identified. These estimates are based on actual claims incurred to date and an estimate of the nature, frequency and costs of future claims. These estimates are inherently uncertain given the Company’s relatively short history of sales, and changes to its historical or projected warranty experience may cause material changes to the warranty reserve in the future. Claims incurred under the Company’s standard product warranty programs are recorded based on open claims. The Company recorded warranty liability within other current liabilities in the consolidated balance sheets as of March 31, 2023 and December 31, 2022.
Concentrations of Credit and Business Risk	Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash accounts in a financial institution, which, at times, may exceed the Federal Depository Insurance Corporation coverage limit of $250,000. As of March 31, 2023 and 2022, the Company has not experienced losses on these accounts and management believes the Company is not exposed to significant risks on such accounts. During the three months ended March 31, 2023, one customer accounted for 82% of the Company’s revenues (gross of customer returns). During the three months ended March 31, 2022, three customers accounted for 24%, 11%, and 10% of the Company’s revenues. As of March 31, 2023, two customers accounted for 59% and 15% of the Company’s accounts receivable. As of March 31, 2023, four customers accounted for 13%, 11%, 11%, and 11% of the Company’s accounts receivable.
Recent Accounting Pronouncements Issued and Adopted and Recent Accounting Pronouncements Issued and Not Yet Adopted	The Company adopted ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"), as amended, on January 1, 2023 using the modified retrospective approach method. As of March 31, 2023 and December 31, 2022 the Company had $27.5 million and $50.6 million, respectively, in marketable debt securities, available for sale which are subject to the new standard. As of January 1, 2023 and March 31, 2023, these marketable debt securities, available for sale have an average credit rating of A and no allowance for expected credit losses has been recorded. Under the modified retrospective approach, the Company would record a cumulative effect adjustment to retained earnings by recording an initial allowance for credit losses on marketable debt securities, available-for sale. Periods presented that are prior to the adoption date of January 1, 2023 will not be adjusted. ASU 2016-13 replaced the incurred loss impairment model with a methodology that reflects a current expected credit loss and made targeted changes to the impairment model for available-for-sale debt securities. ASU 2016-13 impacted all of the Company’s investments held at fair value, which included its marketable debt securities, available for sale. Upon adoption of ASU 2016-13 on January 1, 2023, no adjustment was recorded by the Company for an initial allowance for credit losses on marketable debt securities, available for sale and there was no cumulative effect adjustment to retained earnings. Subsequent increases or decreases in the allowance for credit losses on marketable debt securities, available for sale will be recorded in the Company's condensed consolidated statements of operations and comprehensive loss.ASU 2016-13 also applied to the Company’s other financial assets including loans, trade receivables and other financial assets that have the contractual right to receive cash. These other financial assets were evaluated and the adoption of ASU 2016-13 did not have a material impact on the Company’s condensed consolidated financial statements.

Basis of Presentation and Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2023

Xos, Inc. was initially incorporated on July 29, 2020 as a Cayman Islands exempted company under the name “NextGen Acquisition Corporation” (“NextGen”). On August 20, 2021, the transactions contemplated by the Agreement and Plan of Merger, as amended on May 14, 2021, by and among NextGen, Sky Merger Sub I, Inc., a Delaware corporation and a direct wholly owned subsidiary of NextGen (“Merger Sub”), and Xos, Inc., a Delaware corporation (now known as Xos Fleet, Inc., “Legacy Xos”), were consummated (the “Closing”), whereby Merger Sub merged with and into Legacy Xos, the separate corporate existence of Merger Sub ceased and Legacy Xos became the surviving corporation and a wholly owned subsidiary of NextGen (such transaction the “Merger” and, collectively with the Domestication, the “Business Combination”). As a result, Xos became the publicly traded entity listed on the Nasdaq Global Market.

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and the rules and regulations of the Securities and Exchange Commission (the “SEC”) for interim financial information. They do not include all of the information and footnotes required by U.S. GAAP for complete audited financial statements. The accompanying unaudited condensed

consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Legacy Xos and Xos Services. All significant intercompany accounts and transactions have been eliminated in consolidation.

In the opinion of management, all adjustments (primarily consisting of normal accruals) considered for a fair presentation have been included. Operating results for the three months ended March 31, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements as of and for the years ended December 31, 2022 and 2021 presented in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022 filed with the SEC on March 31, 2023.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the balance sheet date, as well as reported amounts of revenues and expenses during the reporting periods. The areas with significant estimates and judgments include, among others, inventory valuation, incremental borrowing rates for assessing operating and financing lease liabilities, useful lives of property and equipment, contingent earn-out shares liability, stock-based compensation, valuation of convertible debt and related embedded derivatives, common stock warrant liability and product warranty liability. Management bases its estimates on historical experience and on various other assumptions believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results could differ from those estimates, and such differences could be material to the Company’s financial statements.

Accounts Receivable, Net

The Company records unsecured and non-interest bearing accounts receivable at the gross invoice amount, net of any allowance for expected credit losses. The Company maintains its allowance for expected credit losses at a level considered adequate to provide for potential account losses on the balance based on management’s evaluation of past losses, current customer conditions, and the anticipated impact of current economic conditions. The Company recorded an allowance for expected credit losses of $39,000 as of March 31, 2023. No allowance for doubtful accounts was recorded as of March 31, 2022.

Investments in Marketable Debt Securities, Available-for-Sale

The Company maintains a portfolio of investments in a variety of fixed and variable rate debt securities, including U.S. treasuries, corporate debt, asset-backed securities and other, non-U.S. government and supranational bonds and certificate of deposit. The Company considers its investments in marketable debt securities to be available-for-sale, and accordingly, are recorded at their fair values. The Company determines the appropriate classification of investments in marketable debt securities at the time of purchase. Unrealized gains and losses on marketable debt securities, available-for-sale are recorded in Accumulated other comprehensive loss which is included within stockholders’ equity. Interest along with amortization of purchase premiums and accretion of discounts from the purchase date through the estimated maturity date, including consideration of variable maturities and contractual call provisions, are included in other income (expenses), net in the condensed consolidated statements of operations and comprehensive loss. Realized gains and losses on the sale of marketable debt securities, available-for-sale are recorded in Other (expense) income, net. The Company typically invests in highly-rated debt securities, and its investment policy generally limits the amount of credit exposure to any one issuer. The policy requires substantially all investments to be investment grade, with the primary objective of minimizing the potential risk of principal loss. See Note 8 — Investments for additional information.On January 1, 2023, the Company adopted ASU 2016-13, Financial Instruments — Credit Losses which requires that credit losses be presented as an allowance rather than as an impairment write-down. Adoption of the standard had no material impact on its financial statements.The Company reviews quarterly its investment portfolio of all securities in an unrealized loss position to determine if an impairment charge or credit reserve is required. The Company excludes accrued interest from both the fair value and the amortized cost basis of marketable debt securities, available-for-sale, for the purposes of identifying and measuring an impairment. An investment is impaired if the fair value is less than its amortized cost basis. Impairment relating to credit losses is recorded through a reduction in the amortized cost of the security or an allowance for credit losses and credit loss expense (included in selling, general and administrative expense), limited by the amount that the fair value is less than the amortized cost basis. Impairment that has not been recorded as a credit loss is recorded through other comprehensive income (loss), net of applicable taxes. The Company made an accounting policy election to not measure an allowance for credit losses for accrued interest receivables. The Company evaluates write-off of accrued interest receivable at the time credit loss exists for the underlying security. As of March 31, 2023 and 2022, we did not recognize any allowance for expected credit losses or impairment, respectively, on marketable debt securities - available-for-sale.

Warranty Liability

The Company provides customers with a product warranty that assures that the products meet standard specifications and are free for periods typically between 2 to 5 years. The Company accrues warranty reserve for the products sold, which includes its best estimate of the projected costs to repair or replace items under warranties and recalls if identified. These estimates are based on actual claims incurred to date and an estimate of the nature, frequency and costs of future claims. These estimates are inherently uncertain given the Company’s relatively short history of sales, and changes to its historical or projected warranty experience may cause material changes to the warranty reserve in the future. Claims incurred under the Company’s standard product warranty programs are recorded based on open claims. The Company recorded warranty liability within other current liabilities in the consolidated balance sheets as of March 31, 2023 and December 31, 2022.

Concentrations of Credit and Business Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist of cash accounts in a financial institution, which, at times, may exceed the Federal Depository Insurance Corporation coverage limit of $250,000. As of March 31, 2023 and 2022, the Company has not experienced losses on these accounts and management believes the Company is not exposed to significant risks on such accounts.

During the three months ended March 31, 2023, one customer accounted for 82% of the Company’s revenues (gross of customer returns). During the three months ended March 31, 2022, three customers accounted for 24%, 11%, and 10% of the Company’s revenues. As of March 31, 2023, two customers accounted for 59% and 15% of the Company’s accounts receivable. As of March 31, 2023, four customers accounted for 13%, 11%, 11%, and 11% of the Company’s accounts receivable.

Recent Accounting Pronouncements Issued and Adopted and Recent Accounting Pronouncements Issued and Not Yet Adopted

The Company adopted ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments ("ASU 2016-13"), as amended, on January 1, 2023 using the modified retrospective approach method. As of March 31, 2023 and December 31, 2022 the Company had $27.5 million and $50.6 million, respectively, in marketable debt securities, available for sale which are subject to the new standard. As of January 1, 2023 and March 31, 2023, these marketable debt securities, available for sale have an average credit rating of A and no allowance for expected credit losses has been recorded. Under the modified retrospective approach, the Company would record a cumulative effect adjustment to retained earnings by recording an initial allowance for credit losses on marketable debt securities, available-for sale. Periods presented that are prior to the adoption date of January 1, 2023 will not be adjusted. ASU 2016-13 replaced the incurred loss impairment model with a methodology that reflects a current expected credit loss and made targeted changes to the impairment model for available-for-sale debt securities. ASU 2016-13 impacted all of the Company’s investments held at fair value, which included its marketable debt securities, available for sale. Upon adoption of ASU 2016-13 on January 1, 2023, no adjustment was recorded by the Company for an initial allowance for credit losses on marketable debt securities, available for sale and there was no cumulative effect adjustment to retained earnings. Subsequent increases or decreases in the allowance for credit losses on marketable debt securities, available for sale will be recorded in the Company's condensed consolidated statements of operations and comprehensive loss.ASU 2016-13 also applied to the Company’s other financial assets including loans, trade receivables and other financial assets that have the contractual right to receive cash. These other financial assets were evaluated and the adoption of ASU 2016-13 did not have a material impact on the Company’s condensed consolidated financial statements.