Summary of Significant Accounting Policies (Policies)	6 Months Ended	12 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The accompanying condensed consolidated financial statements include the accounts of TOI, its subsidiaries, all of which are controlled by TOI through majority voting control, and variable interest entities (“VIE”) for which TOI (through TOI Management) is the primary beneficiary. The Company consolidates entities in which it has a controlling financial interest based on either the variable interest entity or voting interest model. All significant intercompany balances and transactions have been eliminated in consolidation.	Principles of Consolidation The accompanying consolidated financial statements include the accounts of TOI, its subsidiaries, all of which are controlled by TOI through majority voting control, and variable interest entities (“VIE”) for which TOI (through TOI Management) is the primary beneficiary. The Company consolidates entities in which it has a controlling financial interest based on either the variable interest entity or voting interest model. All significant intercompany balances and transactions have been eliminated in consolidation.
Variable Interest Entities	Variable Interest Entities The Company consolidates entities for which it has a variable interest and is determined to be the primary beneficiary. Noncontrolling interests in less-than-wholly-owned consolidated subsidiaries of the Company are presented as a component of total equity to distinguish between the interests of the Company and the interests of the noncontrolling owners. Revenues, expenses, and net income from these subsidiaries are included in the consolidated amounts as presented on the Condensed Consolidated Statements of Income (Operations). The Company holds variable interests in clinical practices, TOI PCs, for which it cannot legally own, as a result of entering into master services agreements ("MSAs"). As of June 30, 2022, TOI held variable interest in TOI CA, The Oncology Institute FL, LLC, a Professional Corporation ("TOI FL,"), and The Oncology Institute TX, a Professional Corporation ("TOI TX"), all of which are VIEs. The Company is the primary beneficiary of the TOI PCs and thus, consolidates the TOI PCs in its financial statements.	Variable Interest Entities The Company consolidates entities for which it has a variable interest and is determined to be the primary beneficiary. Noncontrolling interests in less-than-wholly-owned consolidated subsidiaries of the Company are presented as a component of total equity to distinguish between the interests of the Company and the interests of the noncontrolling owners. Revenues, expenses, and net income from these subsidiaries are included in the consolidated amounts as presented on the consolidated statements of operations. The Company holds variable interests in clinical practices, TOI PCs, for which it cannot legally own, as a result of entering into master services agreements ("MSAs"). As of December 31, 2021, TOI held variable interest in The Oncology Institute CA, a Professional Corporation (TOI CA) and The Oncology Institute FL, LLC, a Professional Corporation ("TOI FL,"), both of which are VIEs. The Company is the primary beneficiary of the TOI PCs and thus, consolidates the TOI PCs in its financial statements.
Business Combinations	Business Combinations The Company accounts for all transactions that represent business combinations using the acquisition method of accounting under Accounting Standards Codification Topic No. 805, Business Combinations (“ASC 805”). Per ASC 805, the identifiable assets acquired, the liabilities assumed, and any noncontrolling interest in the acquired entity are recognized and measured at their fair values on the date an entity obtains control of the acquiree. Such fair values that are not finalized for reporting periods following the acquisition date are estimated and recorded as provisional amounts. Adjustments to these provisional amounts during the measurement period (defined as the date through which all information required to identify and measure the consideration transferred, the assets acquired, the liabilities assumed, and the noncontrolling interests obtained, limited to one year from the acquisition date) are recorded when identified. Goodwill is determined as the excess of the fair value of the consideration exchanged in the acquisition over the fair value of the net assets acquired. The DFPH-Legacy TOI Business Combination was accounted for as a reverse recapitalization. Under this method of accounting, DFPH was treated as the “acquired” company for accounting purposes and the Business Combination was treated as the equivalent of Legacy TOI issuing stock for the net assets of DFPH, accompanied by a recapitalization. The net assets of DFPH are stated at historical cost, with no goodwill or other intangible assets recorded. Operations prior to the Business Combination were those of TOI Parent.	Business Combinations The Company accounts for all transactions that represent business combinations using the acquisition method of accounting under Accounting Standards Codification Topic No. 805, Business Combinations (“ASC 805”). Per ASC 805, the identifiable assets acquired, the liabilities assumed, and any noncontrolling interest in the acquired entity are recognized and measured at their fair values on the date an entity obtains control of the acquiree. Such fair values that are not finalized for reporting periods following the acquisition date are estimated and recorded as provisional amounts. Adjustments to these provisional amounts during the measurement period (defined as the date through which all information required to identify and measure the consideration transferred, the assets acquired, the liabilities assumed, and the noncontrolling interests obtained, limited to one year from the acquisition date) are recorded when identified. Goodwill is determined as the excess of the fair value of the consideration exchanged in the acquisition over the fair value of the net assets acquired. The DFPH-Legacy TOI Business Combination was accounted for as a reverse recapitalization. Under this method of accounting, DFPH was treated as the “acquired” company for accounting purposes and the Business Combination was treated as the equivalent of Legacy TOI issuing stock for the net assets of DFP, accompanied by a recapitalization. The net assets of DFPH are stated at historical cost, with no goodwill or other intangible assets recorded. Operations prior to the Business Combination were those of TOI Parent.
Segment Reporting	Segment Reporting The Company presents the financial statements by segment in accordance with Accounting Standard Codification Topic No. 280, Segment Reporting (“ASC 280”) to provide investors with transparency into how the chief operating decision maker (“CODM”) manages the business. The Company determined the CODM is its Chief Executive Officer. The CODM reviews financial information and allocates resources across three operating segments: patient care, dispensary, and clinical trials & other. Each of the operating segments is also a reporting segment as described further in Note 20.	Segment ReportingThe Company presents the financial statements by segment in accordance with Accounting Standard Codification Topic No. 280, Segment Reporting (“ASC 280”) to provide investors with transparency into how the chief operating decision maker (“CODM”) manages the business. The Company determined the CODM is its Chief Executive Officer. The CODM reviews financial information and allocates resources across three operating segments: patient care, dispensary, and clinical trials & other.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates under different assumptions or conditions. Significant items subject to such estimates and assumptions include judgements related to revenue recognition, estimated accounts receivable, useful lives and recoverability of long-lived and intangible assets, recoverability of goodwill, fair values of acquired identifiable assets and assumed liabilities in business combinations, fair value of intangible assets and goodwill, fair value of share-based compensation, fair value of liability classified instruments, and judgements related to deferred income taxes.	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates under different assumptions or conditions. Significant items subject to such estimates and assumptions include judgements related to revenue recognition, estimated accounts receivable, useful lives and recoverability of long-lived and intangible assets, recoverability of goodwill, fair values of acquired assets and assumed liabilities in business combinations, fair value of intangible assets and goodwill, fair value of share-based compensation, fair value of liability classified instruments, and judgements related to deferred income taxes.
Net Income (Loss) Per Share	Net Income (Loss) Per Share Basic and diluted net income (loss) per share attributable to common stockholders is presented in conformity with the two-class method required for participating securities. Basic and diluted net income (loss) per share has been retrospectively adjusted for all periods presented prior to the Business Combination. The retroactive adjustment is based on the same number of weighted average shares outstanding in each historical period. Under the two-class method, basic and diluted net income (loss) per share attributable to common stockholders is computed by dividing the basic and diluted net income (loss) attributable to common stockholders by the basic and diluted weighted-average number of shares of common stock outstanding during the period. Diluted net income per share attributable to common stockholders adjusts basic net income per share for the potentially dilutive impact of stock options, restricted stock units, earnout shares (defined in Note 14), public warrants and private placement warrants. For periods where the Company has net losses, diluted net loss per share is the same as basic net loss per share because inclusion of potential common shares in the diluted net loss per share calculation has an antidilutive effect. The treasury stock method is used to calculate the potentially dilutive effect of stock options, RSUs, public warrants and private placement warrants. The earnout shares are contingently issuable; therefore, the earnout shares are excluded from basic and diluted EPS until the market conditions have been met (see more detail on the earnout shares in Note 14). For the periods presented, the public and private placement warrants are out of the money; therefore, the public and private placement warrants are antidilutive and excluded from diluted net income per share.	Net Loss Per Share Basic and diluted net loss per share attributable to common stockholders is presented in conformity with the two-class method required for participating securities. Net loss per share has been retrospectively adjusted for all periods presented prior to the Business Combination. The retroactive adjustment is based on the same number of weighted average shares outstanding in each historical period. Under the two-class method, basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted earnings per share attributable to common stockholders adjusts basic earnings per share for the potentially dilutive impact of stock options, restricted stock units, Earnout Shares and warrants. As the Company has reported losses for all periods presented, all potentially dilutive securities are antidilutive and accordingly, basic net loss per share equals diluted net loss per share.
Fair Value Measurements	Fair Value Measurements The Company accounts for fair value measurements under Accounting Standards Codification Topic No. 820, Fair Value Measurements (“ASC 820”). The Company uses valuation approaches that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The Company determines fair value based on assumptions that market participants would use in pricing an asset or liability in the principal or most advantageous market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following levels (see Note 7 for further discussion): Level 1inputs: Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date. Level 2inputs: Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability. Level 3inputs: Unobservable inputs for the asset or liability used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at measurement date.	Fair Value Measurements The Company accounts for fair value measurements under Accounting Standards Codification Topic No. 820, Fair Value Measurements (“ASC 820”). The Company uses valuation approaches that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The Company determines fair value based on assumptions that market participants would use in pricing an asset or liability in the principal or most advantageous market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following levels (see Note 7 for further discussion): Level 1 inputs: Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date. Level 2 inputs: Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability. Level 3 inputs: Unobservable inputs for the asset or liability used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at measurement date.
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards Leases On January 1, 2022, the Company adopted Accounting Standards Update 2016-02, Leases, with various amendments issued in 2018 and 2019 (collectively, “ASC 842”) using the modified retrospective approach, for leases that existed on January 1, 2022. ASC 842 requires lessees to recognize assets and liabilities for most leases. The Company evaluates whether an arrangement is or contains a lease at contract inception. A lease exists when a contract conveys to the customer the right to control the use of an identified asset for a period of time in exchange for consideration. Upon lease commencement, the date on which a lessor makes the underlying asset available to the Company for use, the Company classifies the lease as either an operating or finance lease. The Company applied certain practical expedients permitted under the transition guidance, including the package of practical expedients, which permits the Company not to reassess its prior conclusions related to lease identification, lease classification, and initial direct costs capitalization. The Company solely acts as a lessee and its leases primarily consist of operating leases for its real estate in the states in which the Company operates. The Company has other operating and financing leases for various clinical and non-clinical equipment. Generally, upon the commencement of a lease, the Company will record a right-of-use (“ROU”) asset and lease liability. An ROU asset represents the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Lease liabilities are measured at the present value of the remaining, fixed lease payments at lease commencement. The Company uses its incremental borrowing rate, based on the information available at the later of adoption, inception, or modification in determining the present value of lease payments. ROU assets are measured at an amount equal to the initial lease liability, plus any prepaid lease payments (less any incentives received) and initial direct costs, at the lease commencement date. The Company has elected to account for lease and non-lease components as a single lease component for all underlying classes of assets. As a result, the fixed payments that would otherwise be allocable to the non-lease components are accounted for as lease payments and included in the measurement of the Company’s right-of-use asset and lease liability. Lease arrangements with an initial term of 12 months or less are considered short-term leases and are not recorded on the balance sheet. The operating lease payments are recognized as an expense on a straight-line basis over the lease term. The lease term includes any period covered by renewal options available that the Company is reasonably certain to exercise and any options to terminate the lease that the Company is not reasonably certain to exercise. The Company displays ROU assets, current lease liabilities, and long term lease liabilities arising from operating leases as separate line items on the condensed consolidated balance sheet. The Company includes ROU assets, current lease liabilities, and long term lease liabilities arising from finance leases within property and equipment, net; accrued expenses and other current liabilities; and other non-current liabilities. As a result of the Company's adoption of ASC 842, the Company recorded an initial adjustment to the opening balance sheet of $16,439 to operating ROU assets, $3,970 to current portion of operating lease liabilities, $13,796 to long term operating lease liabilities, $43 to property and equipment, net; $19 to other current liabilities; and $21 to other non- current liabilities. The impact of ASC 842 was not material to the Condensed Consolidated Statement of Income (Operations). Other In May 2021, the FASB issued Accounting Standards Update 2021-04, Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options (“ASU 2021-04”). The guidance in ASU 2021-04 requires the issuer to treat a modification of an equity-classified written call option that does not cause the option to become liability-classified as an exchange of the original option for a new option. This guidance applies whether the modification is structured as an amendment to the terms and conditions of the option or as termination of the original option and issuance of a new option. The Company adopted ASU 2021-04 as of January 1, 2022. The adoption of this guidance did not have a material impact on the Company’s consolidated financial position or results of operations. Recently Issued Accounting Standards In June 2016, the FASB issued Accounting Standards Update 2016-13, Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”), which changes the way entities recognize impairment of many financial assets by requiring immediate recognition of estimated credit losses expected to occur over their remaining life, instead of when incurred. In November 2018, the FASB issued Accounting Standard Update 2018-19, Codification Improvements to Topic 326, Financial Instruments — Credit Losses (“ASU 2018-19”), which amends Subtopic 326-20 (created by ASU 2016-13) to explicitly state that operating lease receivables are not in the scope of Subtopic 326-20. Additionally, in April 2019, the FASB issued Accounting Standard Update 2019-04, Codification Improvements to Topic 326, Financial Instruments — Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments (“ASU 2019-04”); in May 2019, the FASB issued Accounting Standards Update 2019-05, Financial Instruments — Credit Losses (Topic 326): Targeted Transition Relief (“ASU 2019-05”); and in November 2019, the FASB issued Accounting Standards Update 2019-10, Financial Instruments — Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842): Effective Dates and ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments — Credit Losses (“ASU 2019-10”), to provide further clarifications on certain aspects of ASU 2016-13 and to extend the nonpublic entity effective date of ASU 2016-13. The changes (as amended) are effective for the Company for annual and interim periods in fiscal years beginning after December 15, 2022. An entity may early adopt ASU 2016-13, as amended, for annual and interim periods in fiscal years beginning after December 15, 2018. While the Company expects its allowance for credit losses to increase upon adoption of ASU 2016-13, the Company does not expect the adoption of ASU 2016-13 to have a material effect on its consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (“ASU 2019-12”), which amends ASC 740, Income Taxes. This new standard is intended to simplify accounting for income taxes by removing certain exceptions to the general principles in ASC 740 and amending existing guidance to improve consistent application of ASC 740. The new standard is effective for the Company beginning January 1, 2022, and for interim periods beginning January 1, 2023. The guidance in the new standard has various elements, some of which are applied on a prospective basis and others on a retrospective basis with earlier application permitted. The Company is currently evaluating the effect of ASU 2019-12 on the Company’s consolidated financial statements and related disclosures. In August 2020, the FASB issued ASU 2020-06, Debt-Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity ("ASU 2020-06"), which simplifies accounting for convertible instruments by removing major separation models required under current U.S. GAAP. ASU 2020-06 also removes certain settlement conditions that are required for equity-linked contracts to qualify for the derivative scope exception and it also simplifies the diluted earnings per share calculation in certain areas. The new standard is effective for the Company beginning January 1, 2024. The Company is currently evaluating the effect of ASU 2020-06 on the Company’s consolidated financial statements and related disclosures. In October 2021, the FASB issued ASU 2021-08, Business Combinations: Accounting for Contract Assets and Contract Liabilities from Contracts with Customers ("ASU 2021-08"). Under ASU 2021-08, an acquirer must recognize, and measure contract assets and contract liabilities acquired in a business combination in accordance with ASC 606. The guidance is effective for interim and annual periods beginning after December 15, 2023, with early adoption permitted. The Company will adopt ASU 2021-08 on January 1, 2024 on a prospective basis. The Company does not expect the adoption of this standard to have a material impact on the Company’s consolidated financial statements and related disclosures.	Recently Adopted Accounting Standards In November 2021, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update 2021-10, Government Assistance, Disclosures by Business Entities about Government Assistance ("ASU 2021-10"). The new standard requires additional disclosures regarding government grants and contributions. The standard requires disclosures on the nature of the transactions and related accounting policies, including significant terms and conditions, as well as the amounts and specific financial statement line items affected by the transactions. This standard is effective for fiscal years beginning after December 15, 2021. Early adoption is permitted. The Company elected to early adopt this standard effective January 1, 2021, using the retrospective approach transition method. The adoption of this guidance did not have a material impact on the Company’s consolidated financial position or results of operations. Recently Issued Accounting Standards In February 2016, the FASB issued Accounting Standards Update No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which amends the existing accounting standards for leases. The new standard requires lessees to record a right-of-use (“ROU”) asset and a corresponding lease liability on the balance sheet (with the exception of short-term leases), whereas under current accounting standards the Company’s lease portfolio consists primarily of operating leases and is not recognized on its consolidated balance sheets. The Company will adopt ASC 842 effective January 1, 2022, using the alternative modified transition method and will record a cumulative-effect adjustment to the opening balance of retained earnings as of that date. Prior periods will not be restated. The Company believes the largest impact will be on the consolidated balance sheet for the accounting of facilities-related leases, which represents a majority of its operating leases it has entered into as a lessee. These leases will be recognized under the new standard as ROU assets and operating lease liabilities, which the Company approximates will be $15,800 and $17,100, respectively. The Company will also provide expanded disclosures for its leasing arrangements. The results of operations are not expected to significantly change after adoption of the new standard. In June 2020, the FASB issued Accounting Standards Update 2020-05, Leases (Topic 842), Effective Dates for Certain Entities (“ASU 2020-05”), which deferred the effective dates of ASU 2016-02 in order to respond to the significant business and capital market disruptions caused by the COVID-19 pandemic. In February 2016, the Board issued ASU 2016-02, with an effective date for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, for public business entities. For all other entities, Leases (Topic 842) was effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. In November 2019, the Board issued Accounting Standards Update 2019-10, Financial Instruments — Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842): Effective Dates (“ASU 2019-10”). The amendments in ASU 2019-10 deferred the effective dates for Leases for entities in the “all other” category by an additional year. Therefore, ASU 2016-02 was effective for all other entities for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. The amendments in ASU 2020-05 defer the effective date for one year for entities in the “all other” category that have not yet issued their financial statements (or made financial statements available for issuance) reflecting the adoption of Leases. Therefore, under the amendments, Leases is effective for entities within the “all other” category for fiscal years beginning after December 15, 2021, and interim periods within fiscal years beginning after December 15, 2022. The Company belongs in the “all other” category. In June 2016, the FASB issued Accounting Standards Update 2016-13, Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”), which changes the way entities recognize impairment of many financial assets by requiring immediate recognition of estimated credit losses expected to occur over their remaining life, instead of when incurred. In November 2018, the FASB issued Accounting Standard Update 2018-19, Codification Improvements to Topic 326, Financial Instruments — Credit Losses (“ASU 2018-19”), which amends Subtopic 326-20 (created by ASU 2016-13) to explicitly state that operating lease receivables are not in the scope of Subtopic 326-20. Additionally, in April 2019, the FASB issued Accounting Standard Update 2019-04, Codification Improvements to Topic 326, Financial Instruments — Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments (“ASU 2019-04”), in May 2019, the FASB issued Accounting Standards Update 2019-05, Financial Instruments — Credit Losses (Topic 326): Targeted Transition Relief (“ASU 2019-05”), and in November 2019, the FASB issued Accounting Standards Update 2019-10, Financial Instruments — Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842): Effective Dates, and ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments — Credit Losses (“ASU 2019-10”), to provide further clarifications on certain aspects of ASU 2016-13 and to extend the nonpublic entity effective date of ASU 2016-13. The changes (as amended) are effective for the Company for annual and interim periods in fiscal years beginning after December 15, 2022. The entity may early adopt ASU 2016-13, as amended, for annual and interim periods in fiscal years beginning after December 15, 2018. While the Company expects its allowance for credit losses to increase upon adoption of ASU 2016-13, the Company does not expect the adoption of ASU 2016-13 to have a material effect on its consolidated financial statements. In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (“ASU 2019-12”), which amends ASC 740, Income Taxes. This new standard is intended to simplify accounting for income taxes by removing certain exceptions to the general principles in ASC 740 and amending existing guidance to improve consistent application of ASC 740. The new standard is effective for the Company beginning January 1, 2022. The guidance in the new standard has various elements, some of which are applied on a prospective basis and others on a retrospective basis with earlier application permitted. The Company is currently evaluating the effect of ASU 2019-12 on the Company’s consolidated financial statements and related disclosures. In August 2020, the FASB issued ASU 2020-06, Debt-Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity ("ASU 2020-06"), which simplifies accounting for convertible instruments by removing major separation models required under current U.S. GAAP. ASU 2020-06 also removes certain settlement conditions that are required for equity-linked contracts to qualify for the derivative scope exception and it also simplifies the diluted earnings per share calculation in certain areas. The new standard is effective for the Company beginning January 1, 2024. The Company is currently evaluating the effect of ASU 2020-06 on the Company’s consolidated financial statements and related disclosures. In May 2021, the FASB issued Accounting Standards Update 2021-04, Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options (“ASU 2021-04”). The guidance in ASU 2021-04 requires the issuer to treat a modification of an equity-classified written call option that does not cause the option to become liability-classified as an exchange of the original option for a new option. This guidance applies whether the modification is structured as an amendment to the terms and conditions of the option or as termination of the original option and issuance of a new option. The amendments in this update are effective for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. The Company does not expect the adoption of this standard to have a material impact on its consolidated financial statements and related disclosures. In October 2021, the FASB issued ASU 2021-08, Business Combinations: Accounting for Contract Assets and Contract Liabilities from Contracts with Customers ("ASU 2021-08"). Under ASU 2021-08, an acquirer must recognize, and measure contract assets and contract liabilities acquired in a business combination in accordance with ASC 606. The guidance is effective for interim and annual periods beginning after December 15, 2023, with early adoption permitted. The Company will adopt ASU 2021-08 on January 1, 2024 on a prospective basis. The Company does not expect the adoption of this standard to have a material impact on the Company’s consolidated financial statements and related disclosures.

Summary of Significant Accounting Policies (Policies)

6 Months Ended

12 Months Ended

Jun. 30, 2022

Dec. 31, 2021

The accompanying condensed consolidated financial statements include the accounts of TOI, its subsidiaries, all of which are controlled by TOI through majority voting control, and variable interest entities (“VIE”) for which TOI (through TOI Management) is the primary beneficiary. The Company consolidates entities in which it has a controlling financial interest based on either the variable interest entity or voting interest model. All significant intercompany balances and transactions have been eliminated in consolidation.

Principles of Consolidation

The accompanying consolidated financial statements include the accounts of TOI, its subsidiaries, all of which are controlled by TOI through majority voting control, and variable interest entities (“VIE”) for which TOI (through TOI Management) is the primary beneficiary. The Company consolidates entities in which it has a controlling financial interest based on either the variable interest entity or voting interest model. All significant intercompany balances and transactions have been eliminated in consolidation.

Variable Interest Entities

The Company consolidates entities for which it has a variable interest and is determined to be the primary beneficiary. Noncontrolling interests in less-than-wholly-owned consolidated subsidiaries of the Company are presented as a component of total equity to distinguish between the interests of the Company and the interests of the noncontrolling owners. Revenues, expenses, and net income from these subsidiaries are included in the consolidated amounts as presented on the Condensed Consolidated Statements of Income (Operations).

The Company holds variable interests in clinical practices, TOI PCs, for which it cannot legally own, as a result of entering into master services agreements ("MSAs"). As of June 30, 2022, TOI held variable interest in TOI CA, The Oncology Institute FL, LLC, a Professional Corporation ("TOI FL,"), and The Oncology Institute TX, a Professional Corporation ("TOI TX"), all of which are VIEs. The Company is the primary beneficiary of the TOI PCs and thus, consolidates the TOI PCs in its financial statements.

Variable Interest Entities

The Company holds variable interests in clinical practices, TOI PCs, for which it cannot legally own, as a result of entering into master services agreements ("MSAs"). As of December 31, 2021, TOI held variable interest in The Oncology Institute CA, a Professional Corporation (TOI CA) and The Oncology Institute FL, LLC, a Professional Corporation ("TOI FL,"), both of which are VIEs. The Company is the primary beneficiary of the TOI PCs and thus, consolidates the TOI PCs in its financial statements.

Business Combinations

The Company accounts for all transactions that represent business combinations using the acquisition method of accounting under Accounting Standards Codification Topic No. 805, Business Combinations (“ASC 805”). Per ASC 805, the identifiable assets acquired, the liabilities assumed, and any noncontrolling interest in the acquired entity are recognized and measured at their fair values on the date an entity obtains control of the acquiree. Such fair values that are not finalized for reporting periods following the acquisition date are estimated and recorded as provisional amounts. Adjustments to these provisional amounts during the measurement period (defined as the date through which all information required to identify and measure the consideration transferred, the assets acquired, the liabilities assumed, and the noncontrolling interests obtained, limited to one year from the acquisition date) are recorded when identified. Goodwill is determined as the excess of the fair value of the consideration exchanged in the acquisition over the fair value of the net assets acquired.

The DFPH-Legacy TOI Business Combination was accounted for as a reverse recapitalization. Under this method of accounting, DFPH was treated as the “acquired” company for accounting purposes and the Business Combination was treated as the equivalent of Legacy TOI issuing stock for the net assets of DFPH, accompanied by a recapitalization. The net assets of DFPH are stated at historical cost, with no goodwill or other intangible assets recorded. Operations prior to the Business Combination were those of TOI Parent.

Business Combinations

The DFPH-Legacy TOI Business Combination was accounted for as a reverse recapitalization. Under this method of accounting, DFPH was treated as the “acquired” company for accounting purposes and the Business Combination was treated as the equivalent of Legacy TOI issuing stock for the net assets of DFP, accompanied by a recapitalization. The net assets of DFPH are stated at historical cost, with no goodwill or other intangible assets recorded. Operations prior to the Business Combination were those of TOI Parent.

Segment Reporting

The Company presents the financial statements by segment in accordance with Accounting Standard Codification Topic No. 280, Segment Reporting (“ASC 280”) to provide investors with transparency into how the chief operating decision maker (“CODM”) manages the business. The Company determined the CODM is its Chief Executive Officer. The CODM reviews financial information and allocates resources across three operating segments: patient care, dispensary, and clinical trials & other. Each of the operating segments is also a reporting segment as described further in Note 20.

Segment ReportingThe Company presents the financial statements by segment in accordance with Accounting Standard Codification Topic No. 280, Segment Reporting (“ASC 280”) to provide investors with transparency into how the chief operating decision maker (“CODM”) manages the business. The Company determined the CODM is its Chief Executive Officer. The CODM reviews financial information and allocates resources across three operating segments: patient care, dispensary, and clinical trials & other.

Use of Estimates

The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the

reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates under different assumptions or conditions. Significant items subject to such estimates and assumptions include judgements related to revenue recognition, estimated accounts receivable, useful lives and recoverability of long-lived and intangible assets, recoverability of goodwill, fair values of acquired identifiable assets and assumed liabilities in business combinations, fair value of intangible assets and goodwill, fair value of share-based compensation, fair value of liability classified instruments, and judgements related to deferred income taxes.

Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates under different assumptions or conditions. Significant items subject to such estimates and assumptions include judgements related to revenue recognition, estimated accounts receivable, useful lives and recoverability of long-lived and intangible assets, recoverability of goodwill, fair values of acquired assets and assumed liabilities in business combinations, fair value of intangible assets and goodwill, fair value of share-based compensation, fair value of liability classified instruments, and judgements related to deferred income taxes.

Net Income (Loss) Per Share

Basic and diluted net income (loss) per share attributable to common stockholders is presented in conformity with the two-class method required for participating securities. Basic and diluted net income (loss) per share has been retrospectively adjusted for all periods presented prior to the Business Combination. The retroactive adjustment is based on the same number of weighted average shares outstanding in each historical period.

Under the two-class method, basic and diluted net income (loss) per share attributable to common stockholders is computed by dividing the basic and diluted net income (loss) attributable to common stockholders by the basic and diluted weighted-average number of shares of common stock outstanding during the period. Diluted net income per share attributable to common stockholders adjusts basic net income per share for the potentially dilutive impact of stock options, restricted stock units, earnout shares (defined in Note 14), public warrants and private placement warrants. For periods where the Company has net losses, diluted net loss per share is the same as basic net loss per share because inclusion of potential common shares in the diluted net loss per share calculation has an antidilutive effect.

The treasury stock method is used to calculate the potentially dilutive effect of stock options, RSUs, public warrants and private placement warrants. The earnout shares are contingently issuable; therefore, the earnout shares are excluded from basic and diluted EPS until the market conditions have been met (see more detail on the earnout shares in Note 14). For the periods presented, the public and private placement warrants are out of the money; therefore, the public and private placement warrants are antidilutive and excluded from diluted net income per share.

Net Loss Per Share

Basic and diluted net loss per share attributable to common stockholders is presented in conformity with the two-class method required for participating securities. Net loss per share has been retrospectively adjusted for all periods presented prior to the Business Combination. The retroactive adjustment is based on the same number of weighted average shares outstanding in each historical period.

Under the two-class method, basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted earnings per share attributable to common stockholders adjusts basic earnings per share for the potentially dilutive impact of stock options, restricted stock units, Earnout Shares and warrants.

As the Company has reported losses for all periods presented, all potentially dilutive securities are antidilutive and accordingly, basic net loss per share equals diluted net loss per share.

Fair Value Measurements

The Company accounts for fair value measurements under Accounting Standards Codification Topic No. 820, Fair Value Measurements (“ASC 820”). The Company uses valuation approaches that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The Company determines fair value based on assumptions that market participants would use in pricing an asset or liability in the principal or most advantageous market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following levels (see Note 7 for further discussion):

Level 1inputs: Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date.

Level 2inputs: Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability.

Level 3inputs: Unobservable inputs for the asset or liability used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at measurement date.

Fair Value Measurements

Level 1 inputs: Unadjusted quoted prices in active markets for identical assets or liabilities accessible to the reporting entity at the measurement date.

Level 2 inputs: Other than quoted prices included in Level 1 inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the asset or liability.

Level 3 inputs: Unobservable inputs for the asset or liability used to measure fair value to the extent that observable inputs are not available, thereby allowing for situations in which there is little, if any, market activity for the asset or liability at measurement date.

Recently Adopted Accounting Standards

Leases

On January 1, 2022, the Company adopted Accounting Standards Update 2016-02, Leases, with various amendments issued in 2018 and 2019 (collectively, “ASC 842”) using the modified retrospective approach, for leases that existed on January 1, 2022. ASC 842 requires lessees to recognize assets and liabilities for most leases. The Company evaluates whether an arrangement is or contains a lease at contract inception. A lease exists when a contract conveys to the customer the right to control the use of an identified asset for a period of time in exchange for consideration. Upon lease commencement, the date on which a lessor makes the underlying asset available to the Company for use, the Company classifies the lease as either an operating or finance lease. The Company applied certain practical expedients permitted under the transition guidance, including the package of practical expedients, which permits the Company not to reassess its prior conclusions related to lease identification, lease classification, and initial direct costs capitalization. The Company solely acts as a lessee and its leases primarily consist of operating leases for its real estate in the states in which the Company operates. The Company has other operating and financing leases for various clinical and non-clinical equipment.

Generally, upon the commencement of a lease, the Company will record a right-of-use (“ROU”) asset and lease liability. An ROU asset represents the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Lease liabilities are measured at the present value of the remaining, fixed lease payments at lease commencement. The Company uses its incremental borrowing rate, based on the information available at the later of adoption, inception, or modification in determining the present value of lease payments. ROU assets are measured at an amount equal to the initial lease liability, plus any prepaid lease payments (less any incentives received) and initial direct costs, at the lease commencement date. The Company has elected to account for lease and non-lease components as a single lease component for all underlying classes of assets. As a result, the fixed payments that would otherwise be allocable to the non-lease components are accounted for as lease payments and included in the measurement of the Company’s right-of-use asset and lease liability.

Lease arrangements with an initial term of 12 months or less are considered short-term leases and are not recorded on the balance sheet. The operating lease payments are recognized as an expense on a straight-line basis over the lease term. The lease term includes any period covered by renewal options available that the Company is reasonably certain to exercise and any options to terminate the lease that the Company is not reasonably certain to exercise.

The Company displays ROU assets, current lease liabilities, and long term lease liabilities arising from operating leases as separate line items on the condensed consolidated balance sheet. The Company includes ROU assets, current lease liabilities, and long term lease liabilities arising from finance leases within property and equipment, net; accrued expenses and other current liabilities; and other non-current liabilities. As a result of the Company's adoption of ASC 842, the Company recorded an initial adjustment to the opening balance sheet of $16,439 to operating ROU assets, $3,970 to current portion of operating lease liabilities, $13,796 to long term operating lease liabilities, $43 to property and equipment, net; $19 to other current liabilities; and $21 to other non-

current liabilities. The impact of ASC 842 was not material to the Condensed Consolidated Statement of Income (Operations).

Other

In May 2021, the FASB issued Accounting Standards Update 2021-04, Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options (“ASU 2021-04”). The guidance in ASU 2021-04 requires the issuer to treat a modification of an equity-classified written call option that does not cause the option to become liability-classified as an exchange of the original option for a new option. This guidance applies whether the modification is structured as an amendment to the terms and conditions of the option or as termination of the original option and issuance of a new option. The Company adopted ASU 2021-04 as of January 1, 2022. The adoption of this guidance did not have a material impact on the Company’s consolidated financial position or results of operations.

Recently Issued Accounting Standards

In June 2016, the FASB issued Accounting Standards Update 2016-13, Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”), which changes the way entities recognize impairment of many financial assets by requiring immediate recognition of estimated credit losses expected to occur over their remaining life, instead of when incurred. In November 2018, the FASB issued Accounting Standard Update 2018-19, Codification Improvements to Topic 326, Financial Instruments — Credit Losses (“ASU 2018-19”), which amends Subtopic 326-20 (created by ASU 2016-13) to explicitly state that operating lease receivables are not in the scope of Subtopic 326-20. Additionally, in April 2019, the FASB issued Accounting Standard Update 2019-04, Codification Improvements to Topic 326, Financial Instruments — Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments (“ASU 2019-04”); in May 2019, the FASB issued Accounting Standards Update 2019-05, Financial Instruments — Credit Losses (Topic 326): Targeted Transition Relief (“ASU 2019-05”); and in November 2019, the FASB issued Accounting Standards Update 2019-10, Financial Instruments — Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842): Effective Dates and ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments — Credit Losses (“ASU 2019-10”), to provide further clarifications on certain aspects of ASU 2016-13 and to extend the nonpublic entity effective date of ASU 2016-13. The changes (as amended) are effective for the Company for annual and interim periods in fiscal years beginning after December 15, 2022. An entity may early adopt ASU 2016-13, as amended, for annual and interim periods in fiscal years beginning after December 15, 2018. While the Company expects its allowance for credit losses to increase upon adoption of ASU 2016-13, the Company does not expect the adoption of ASU 2016-13 to have a material effect on its consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (“ASU 2019-12”), which amends ASC 740, Income Taxes. This new standard is intended to simplify accounting for income taxes by removing certain exceptions to the general principles in ASC 740 and amending existing guidance to improve consistent application of ASC 740. The new standard is effective for the Company beginning January 1, 2022, and for interim periods beginning January 1, 2023. The guidance in the new standard has various elements, some of which are applied on a prospective basis and others on a retrospective basis with earlier application permitted. The Company is currently evaluating the effect of ASU 2019-12 on the Company’s consolidated financial statements and related disclosures.

In August 2020, the FASB issued ASU 2020-06, Debt-Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity ("ASU 2020-06"), which simplifies accounting for convertible instruments by removing major separation models required under current U.S. GAAP. ASU 2020-06 also removes certain settlement conditions that are required for equity-linked contracts to qualify for the derivative scope exception and it also simplifies the diluted earnings per share calculation in certain areas. The new standard is effective for the Company beginning January 1, 2024. The Company is currently evaluating the effect of ASU 2020-06 on the Company’s consolidated financial statements and related disclosures.

In October 2021, the FASB issued ASU 2021-08, Business Combinations: Accounting for Contract Assets and Contract Liabilities from Contracts with Customers ("ASU 2021-08"). Under ASU 2021-08, an acquirer must recognize, and measure contract assets and contract liabilities acquired in a business combination in accordance with ASC 606. The guidance is effective for interim and annual periods beginning after December 15, 2023, with early adoption permitted. The Company will adopt ASU 2021-08 on January 1, 2024 on a prospective basis. The Company does not expect the adoption of this standard to have a material impact on the Company’s consolidated financial statements and related disclosures.

Recently Adopted Accounting Standards

In November 2021, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update 2021-10, Government Assistance, Disclosures by Business Entities about Government Assistance ("ASU 2021-10"). The new standard requires additional disclosures regarding government grants and contributions. The standard requires disclosures on the nature of the transactions and related accounting policies, including significant terms and conditions, as well as the amounts and specific financial statement line items affected by the transactions. This standard is effective for fiscal years beginning after December 15, 2021. Early adoption is permitted. The Company elected to early adopt this standard effective January 1, 2021, using the retrospective approach transition method. The adoption of this guidance did not have a material impact on the Company’s consolidated financial position or results of operations.

Recently Issued Accounting Standards

In February 2016, the FASB issued Accounting Standards Update No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which amends the existing accounting standards for leases. The new standard requires lessees to record a right-of-use (“ROU”) asset and a corresponding lease liability on the balance sheet (with the exception of short-term leases), whereas under current accounting standards the Company’s lease portfolio consists primarily of operating leases and is not recognized on its consolidated balance sheets. The Company will adopt ASC 842 effective January 1, 2022, using the alternative modified transition method and will record a cumulative-effect adjustment to the opening balance of retained earnings as of that date. Prior periods will not be restated. The Company believes the largest impact will be on the consolidated balance sheet for the accounting of facilities-related leases, which represents a majority of its operating leases it has entered into as a lessee. These leases will be recognized under the new standard as ROU assets and operating lease liabilities, which the Company approximates will be $15,800 and $17,100, respectively. The Company will also provide expanded disclosures for its leasing arrangements. The results of operations are not expected to significantly change after adoption of the new standard.

In June 2020, the FASB issued Accounting Standards Update 2020-05, Leases (Topic 842), Effective Dates for Certain Entities (“ASU 2020-05”), which deferred the effective dates of ASU 2016-02 in order to respond to the significant business and capital market disruptions caused by the COVID-19 pandemic. In February 2016, the Board issued ASU 2016-02, with an effective date for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, for public business entities. For all other entities, Leases (Topic 842) was effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. In November 2019, the Board issued Accounting Standards Update 2019-10, Financial Instruments — Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842): Effective

Dates (“ASU 2019-10”). The amendments in ASU 2019-10 deferred the effective dates for Leases for entities in the “all other” category by an additional year. Therefore, ASU 2016-02 was effective for all other entities for fiscal years beginning after December 15, 2020, and interim periods within fiscal years beginning after December 15, 2021. The amendments in ASU 2020-05 defer the effective date for one year for entities in the “all other” category that have not yet issued their financial statements (or made financial statements available for issuance) reflecting the adoption of Leases. Therefore, under the amendments, Leases is effective for entities within the “all other” category for fiscal years beginning after December 15, 2021, and interim periods within fiscal years beginning after December 15, 2022. The Company belongs in the “all other” category.

In June 2016, the FASB issued Accounting Standards Update 2016-13, Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”), which changes the way entities recognize impairment of many financial assets by requiring immediate recognition of estimated credit losses expected to occur over their remaining life, instead of when incurred. In November 2018, the FASB issued Accounting Standard Update 2018-19, Codification Improvements to Topic 326, Financial Instruments — Credit Losses (“ASU 2018-19”), which amends Subtopic 326-20 (created by ASU 2016-13) to explicitly state that operating lease receivables are not in the scope of Subtopic 326-20. Additionally, in April 2019, the FASB issued Accounting Standard Update 2019-04, Codification Improvements to Topic 326, Financial Instruments — Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments (“ASU 2019-04”), in May 2019, the FASB issued Accounting Standards Update 2019-05, Financial Instruments — Credit Losses (Topic 326): Targeted Transition Relief (“ASU 2019-05”), and in November 2019, the FASB issued Accounting Standards Update 2019-10, Financial Instruments — Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842): Effective Dates, and ASU 2019-11, Codification Improvements to Topic 326, Financial Instruments — Credit Losses (“ASU 2019-10”), to provide further clarifications on certain aspects of ASU 2016-13 and to extend the nonpublic entity effective date of ASU 2016-13. The changes (as amended) are effective for the Company for annual and interim periods in fiscal years beginning after December 15, 2022. The entity may early adopt ASU 2016-13, as amended, for annual and interim periods in fiscal years beginning after December 15, 2018. While the Company expects its allowance for credit losses to increase upon adoption of ASU 2016-13, the Company does not expect the adoption of ASU 2016-13 to have a material effect on its consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (“ASU 2019-12”), which amends ASC 740, Income Taxes. This new standard is intended to simplify accounting for income taxes by removing certain exceptions to the general principles in ASC 740 and amending existing guidance to improve consistent application of ASC 740. The new standard is effective for the Company beginning January 1, 2022. The guidance in the new standard has various elements, some of which are applied on a prospective basis and others on a retrospective basis with earlier application permitted. The Company is currently evaluating the effect of ASU 2019-12 on the Company’s consolidated financial statements and related disclosures.

In May 2021, the FASB issued Accounting Standards Update 2021-04, Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options (“ASU 2021-04”). The guidance in ASU 2021-04 requires the issuer to treat a modification of an equity-classified written call option that does not cause the option to become liability-classified as an exchange of the original option for a new option. This guidance applies whether the modification is structured as an amendment to the terms and conditions of the option or as termination of the original option and issuance of a new option. The amendments in this update are effective for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. The Company does not expect the adoption of this standard to have a material impact on its consolidated financial statements and related disclosures.