NASDAQ: TOIIW

Through this network, TOI managed a population of approximately 2.0 million patients under value-based agreements as of December 31, 2025.

Our Business Lines

Patient Services

Fee for Service

TOI provides medical care on a fee-for service basis for physician services, in-house infusion, radiation, and innovative programs like outpatient blood product transfusions, along with 24/7 patient support. The services TOI provides in its fee for service business are generally covered under commercial and government managed care programs, which are billed retrospectively for care provided in clinics, following a typically small patient co-pay collected at the time of service. We customarily bill for physician and infusion services on a CPT-code basis, and for drugs on a cost-plus basis. We are generally reliant on outside referrals of these fee-for-service patients, who may be in the care of a primary care provider, non-oncology specialist physician, or hospitalist, who then refers the patient upon diagnosis to an oncology provider within TOI. We generate these referrals based on the reputation of our doctors and our platform within the communities we serve, as well as our active and direct referrer education efforts.

Value-based

TOI offers value-based contracts to payors, including managed care organizations and other risk-bearing entities, who are interested in transferring both the risk and responsibility for managing outpatient oncology care to us. These arrangements can take multiple different forms, but typically involve a population-level assignment, where TOI receives 100% share of a patient population and is paid either a fixed amount per member on a regular (typically monthly) schedule, or, less commonly, is paid/recoups a portion of gains/losses at the end of a measurement period. In this way, TOI receives a predictable, recurring payment for oncology care, and generates a profit to the extent the actual cost of oncology care for our contracted patient populations is less than this fixed payment. Generally, we are able to offer fixed payments to payors that represent a discount to the historical oncology cost and/or cost trend for these patient populations, while still generating positive profitability for TOI. We do this through active management of clinical pathways and drug formulary, incorporating best clinical practices and recognized quality metrics, using both our affiliated and MSO clinics, as well as negotiating network contracts with third-party providers. TOI's decade-plus of experience efficiently managing oncology populations, intensive clinical interventions, and TOI's comprehensive knowledge of therapeutic options across both pharmaceuticals and radiation therapy position us to effectively manage these contracts in a way that adds value to both our payor partners and patients.

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Specialty Pharmacy

TOI operates specialty and retail pharmacies in all 5 states through which we are capable of filling medication orders that are incidental or coincidental to our patients' oncology care. Often patients undergoing outpatient oncology treatment are receiving a combination of IV-infused, oral, and injectable medications, for oncology treatment as well as other co-occurring conditions, making our populations particularly relevant for pharmacy services on therapeutics that are not provider-administered within the clinic and therefore would typically fall outside of our traditional Patient Services fee for service business. Because of the relationship derived from the repeated visits and close consultation that occurs during treatment for an active oncology episode, our patients develop a relationship to providers in the TOI clinics, as well as a cadence of regular visits. This provides TOI a complementary opportunity to service these patients by ordering and filling oral, IV, and injectable medications that the patients frequently self-administer or have administered inside or outside of TOI's clinics. For these medications, we are typically billing patients' pharmacy benefit managers, which are generally incorporated within patients' managed care plans, whether commercial or government. Pharmacy claims are generally billed at the time medication is ordered, along with a customary patient co-pay, which TOI seeks to collect at the time of pickup. Reimbursement for the pharmacy is generally calculated using a wholesale acquisition cost, or WAC-minus basis, which is on average a higher rate than TOI is able to procure the medication from its vendors.

Clinical Trials and Other

Through TOI Clinical Research, LLC ("TCR"), the clinical research arm of our affiliated professional corporations, or TOI PCs, we also provide and manage clinical trial services and research for the benefit of cancer patients, as well as palliative care for patients in the last stages of disease. Many of our services, such as managing clinical trials and palliative care programs, are traditionally accessed through academic and tertiary care settings, while the TOI PCs bring these services to patients in a community setting, by which we mean, providing care in our convenient clinic locations rather than academic or tertiary care settings. Revenue in our clinical trials business is billed to pharmaceutical companies or the contract research organizations engaged by pharmaceutical companies to administer their trials, and paid in arrears based on which individual medical procedures were performed on enrolled patients during the course of the trial. See Note 1 of the consolidated financial statements for the profit sharing arrangement TOI entered into in 2025 with Helios Clinical Research.

Our Mission

As a value-based oncology company, we seek to deliver better quality care while managing costs for patients and payors that we serve. We define value-based care as care that focuses on providing optimal health outcomes and healthcare affordability and a value-based contract as any contract that removes the incentive to drive up cost of care or overutilization, while rewarding better clinical outcomes, cost and quality. We work to accomplish this goal by reducing wasteful, inefficient or futile care that drives up costs but does not improve outcomes. We believe payors and employers are aligned with the value-based model due to its enhanced access, improved outcomes, and lower costs. Patients under our affiliated providers’ care can benefit from evidence-based and personalized care plans, gain access to sub-specialized care in convenient community

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locations, and lower out-of-pocket costs. We believe our affiliated providers enjoy the stability and predictability of a large multi-state practice, are not incentivized or pressured to over-treat when it may be inconsistent with a patient’s goals of care and can focus on practicing outstanding evidence-based oncology care.

In contrast to value-based care, we believe much of traditional fee-for-service, or FFS, oncology care is plagued by misaligned incentives that drive up costs and often lower the quality of care. In FFS care, oncologists are reimbursed on a “cost-plus” basis for drugs which in turn are often responsible for the majority of a practice’s revenue. This "cost-plus" model may incentivize oncologists to prescribe the most expensive treatments even if lower cost alternatives that are still medically appropriate are available, as well as to continue to utilize chemotherapy in advanced cancer patients who may no longer benefit from such treatment. In these cases, patients and payors not only bear the burden of higher cost of care, but patients may also suffer negative health outcomes including higher rates of emergency room visits and hospitalizations for supportive care needs due to the side effects associated with chemotherapy.

In 2025, we generated more than 46% of our revenue from patients who are covered by value-based contracts. Historically, our value-based contracts have predominantly taken the form of capitated contracts. Our capitated contracts remove incentives to drive up costs, and they also have incentives for meeting or exceeding certain quality metrics. In some capitated contracts we are penalized if we fail to meet certain quality metrics. In other capitated contracts, we receive bonuses/rewards if we meet or exceed certain quality metrics. Our value-based contracts could also take on other forms, such as sharing with payors in the cost savings generated for specific medical oncology costs (which we refer to as 'gain-sharing' contracts), along with incentives to meet certain quality metrics. These contracts, despite their modifications on how reimbursement is structured, still meet the definition of value-based care. We and our affiliated providers have contractual relationships with payors serving a variety of patients, including Medicare Advantage ("MA"), Medicaid, and commercial patients. These payors include affiliates of Anthem, CareMore Health, Heritage Provider Network and Optum Care.

In 2025, we continued to evolve the way we structure our value-based arrangements, particularly in areas of the country where there is an increased desire and capability from managed care groups to fully delegate traditional managed care services for the treatment of oncology to providers like TOI. Under this model, which we refer to as "full delegation" TOI performs not only the traditional function of care provider for a portion of patients, but also functions more classically executed by the managed care industry, including utilization management, network construction, and claims adjudication. Under this full delegation model, TOI is paid a capitation by the payor on a similar per-member, per-month basis as TOI's traditional capitation model. Using these funds, TOI is then responsible for management of the oncology care for patients seen at both TOI clinics, as well as at independent clinics within the network constructed and managed by TOI. With both TOI and network providers, TOI is responsible for authorizing and paying relevant claims. We believe that these new contracting methodologies are furthering our mission to provide access to world-class oncology care, in an affordable manner, to underserved populations, allowing us to be an even more engaged partner to our payors for populations beyond those serviced directly in a TOI clinic.

We believe that our position in the market and focus on elevating the state of oncology care with a value-based care model positions our affiliated providers well for future growth. Our technology platform supports this growth and enables the TOI PCs to standardize and deliver consistent value-based care at scale. We believe that our model will support growth into new markets, and allow us to continue to service more patients across the United States.

Our website is www.theoncologyinstitute.com. The information contained on our website is not a part of this annual report.

Affiliated Physician Practices

Some states have laws that prohibit business entities with non-physician owners from practicing medicine, which are generally referred to as the corporate practice of medicine. States that have corporate practice of medicine laws require only physicians to practice medicine, exercise control over medical decisions or engage in certain arrangements with other physicians, such as fee-splitting. For example, under California's corporate practice of medicine doctrine, physicians and certain licensed professionals cannot be employed by non-professional corporations, except under limited exceptions which do not apply to us. Additionally, all clinical decisions and certain business or management decisions that result in control over a physician's practice of medicine must be made by a licensed physician and not by an unlicensed person or entity. California also prohibits professional fee-splitting arrangements, but management fees based on a percentage of gross revenue or similar arrangement that is commensurate with fair market value of services provided by the management company are generally permissible.

We have entered into a management services agreement with each of the TOI PCs, which are entirely physician owned. Under our management services agreements, we have agreed to serve, on an exclusive basis, as manager and administrator of each TOI PC’s non-medical functions and services related to healthcare services and items provided to patients by physicians and other licensed healthcare providers employed by or under contract with a TOI PC. The non-medical functions and services we provide under the management services agreements include practice management services and non-clinical operational

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assistance for all TOI PC clinic locations, assistance with provider and payor contract negotiations and administration, billing and collection services, financial and accounting services, electronic medical records and practice management technology solutions, assistance in maintaining licensure, permits and other credentialing requirements for the TOI PCs, risk management services, non-clinical personnel services, provider recruitment services and other administrative services required for the day-to-day operations of the clinics and TOI PCs. Our management services agreements with the TOI PCs have 20-year terms, unless terminated upon mutual agreement of the parties or unilaterally by a party following a material breach or commencement of bankruptcy or liquidation events by the other party, or a governmental or judicial termination order against a party. Under the management services agreement, we receive a monthly management fee that is structured as direct reimbursement of all costs incurred plus a percentage of the TOI PC’s gross revenue, which is defined as the TOI PC’s total revenues payable for all healthcare services and items rendered by the TOI PC, adjusted for bad debt, discounts and payor contract adjustments. In accordance with relevant accounting guidance, each of the TOI PCs is determined to be a variable interest entity, or VIE, of the Company as the Company has the ability, through the management services agreement, to direct the activities (excluding clinical decisions) that most significantly affect the TOI PC’s economic performance.

We have entered into stock transfer restriction agreements with the physician shareholders of each of the TOI PCs. Under the stock transfer agreements, the shareholder is restricted from transferring (voluntarily or involuntarily) his or her shares in the applicable TOI PC and its subsidiaries. Upon the occurrence of certain events, including the shareholder’s death, disqualification from the practice of medicine or participation in Medicare or any other federal or state government healthcare programs, termination of employment with the TOI PC, suspension of his or her medical license, being charged with or convicted of certain crimes, the shares will be immediately transferred for a nominal amount to a qualified physician designated by us. Concurrently with any such transfer, the shareholder will be deemed to have resigned as a director and officer of the TOI PC. In addition, the shareholder agrees not to cause the TOI PC to issue any dividends, to amend any governing documents of the TOI PC, or to enter into any sale, merger or similar agreement. We have also entered into medical director agreements with each physician under which the physician provides certain administrative services to the TOI PCs on our behalf for nominal compensation. Each of the medical director agreements may be terminated by either party for convenience.

Market Overview

Our business is focused on caring for adult and senior populations with medical oncology and related care needs, including members of MA plans run by private insurance companies on behalf of the Centers for Medicare and Medicaid Services, or CMS, as well as traditional FFS Medicare, Medicaid, other government healthcare programs and commercial insurance populations. One of our primary focuses is on value-based contracts in which we manage the medical oncology care for a population of patients for a pre-determined, population-based capitated payment. Many of the patients that we manage under value-based arrangements are referred to as “capitated” populations, however our affiliated providers also provide care to patients outside of these arrangements under traditional FFS arrangements as well as other types of value-based contract.

Our Care Model

Since our founding over 15 years ago, we have built a solid track record around our comprehensive, community-based care model for value-based oncology care. Our care model is focused on delivering personalized, evidenced-based care, consistently, and at scale. We seek to deliver better patient outcomes for lower costs, and to care for more of our payors’ patient populations.

Our care model is designed to remove physicians’ incentives to over-prescribe or prescribe high-cost chemotherapy that is of limited clinical utility to patients, but rather focus on adherence to National Comprehensive Cancer Network ("NCCN") guidelines and, when possible, choose clinically equivalent but lower-cost therapeutics to benefit patients and our payor partners. We invest in nurse practitioners to help with advanced care planning and palliative care discussions with patients. We give patients the education and tools to make their own decisions about when the right time is to choose palliative care or hospice.

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While the TOI PCs treat patients under both value-based and FFS contracts, our affiliated providers’ approach to care focuses on achieving the best outcomes at the lowest cost, regardless of the reimbursement methodology. We have developed a High Value Cancer Care, or HVCC, program, in which patients are able to access targeted care resources that augment and support their treatment. Our treatment regimens are based on algorithms established by the NCCN and are evidence-based. NCCN is a not-for-profit alliance of 32 leading cancer centers devoted to patient care, research and education (not including TOI). NCCN focuses on improving cancer care through the input of clinical thought leaders at its member organizations. NCCN publishes guidelines developed from evidence- based medicine to ensure that all cancer patients receive preventative, diagnostic, treatment, and supportive services that are most likely to lead to optimal outcomes. The NCCN guidelines are widely recognized as the standard for clinical care in medical oncology, and the intent of the guidelines is to assist in clinical decision making. Our affiliated providers strive to ensure that clinical pathways in our electronic health records system, as well as recommendations on use of chemotherapy and supportive care medications are consistent with NCCN guidelines to ensure patients receive the best clinical care based on their individual disease and comorbidities. Moreover, the TOI PCs operate physician dispensaries that allow our affiliated providers to prescribe and dispense oral oncology and related medications to patients, alongside chemotherapy infusion and injections. This provides patients with holistic and convenient access to the most appropriate treatment pathways, all in a community setting. According to a study conducted by researchers at Stanford University on the TOI PCs’ patients in 2019 who were enrolled in our HVCC program, we saw improvements in several key metrics, including:

Overall, the study demonstrated greater than 25% lower median total healthcare costs from diagnosis to death. We are continuously improving and innovating our care model, using the clinical data from the HVCC program to develop evidence-based care and treatment protocols for all patients.

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Our Value Proposition and Differentiated Care Model

Our managed clinics primarily serve adult and senior cancer patients in markets that have MA plans and primary care medical groups reimbursed on a capitated basis. Our affiliated providers provide these services primarily through employed providers who are responsible for patient care. We intend to leverage our long-established, strong relationships with payors to continue to build out our network and increase access to cancer patients in adjacent markets, while at the same time, decreasing oncology care costs for both patients and payors. Through the TOI PCs, we seek to provide high quality and lower cost care delivery through the following capabilities:

•recruiting process focused on selecting physicians that want to practice evidence-based medicine;

•technology-enabled care pathways ensuring adherence to evidence-based clinical protocols;

•strong clinical culture and physician oversight;

•care management to prevent unnecessary hospitalizations;

•care delivered in community clinics vs. hospital setting;

•clinically appropriate integration of palliative care and hospice aligned with patients’ goals of care;

•access to clinical trials providing cutting-edge treatment options at low or no cost to patients or payors; and

•appropriate provider training on clinical documentation to ensure proper risk adjustment and reimbursement for complex patients.

We strive to add value by consistently performing these activities effectively. The goal is a lower cost of care for the same or better clinical outcomes while providing a superior patient experience.

Patient Experience

We believe our patient-centric focus facilitates high levels of patient satisfaction and supports our care delivery model while strengthening payor relationships. We employ a continuous feedback mechanism to ensure superior patient experience and satisfaction among our affiliated physicians and advanced practice providers.

Based on the latest 3,500+ Google reviews we have an average patient rating of 4.6 out of 5 stars.

Growth Strategy and Opportunities

Our footprint as of December 31, 2025 spanned five states and is growing rapidly.

California

Arizona

Nevada

Florida
Oregon

Markets
71153

Affiliated Clinics(1)
4143143

Affiliated Providers
8146205

Network Providers(2)
11——187—

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(1) Clinics operated under the TOI PCs, whereby we receive a percentage of revenues under our management services agreements, or MSAs, and are consolidated

(2) 67 independent oncology practice locations participating in TOI's Florida Oncology Network for participation in patient services covered under TOI's fully delegated contracts

We anticipate adding more TOI PC clinics in the future across our new and existing markets through acquisitions and de novo clinic builds, as well as network providers through our network contracting strategy which allows for asset-lite expansion. We are in constant discussion with payors and providers to enter new markets and we continually seek to evaluate our growth strategy and may continue to modify it in the future, and there can be no assurance that we will be able to successfully capitalize on growth strategies.

Our go-to-market strategy focuses on both payors and providers. This blend is important given the increasing penetration of non-traditional payors, such as Oscar and Bright HealthCare, and primary care risk models such as Agilon health and ChenMed LLC.

We believe that our existing payor relationships provide us leads on opportunities to enter new markets, and we often receive outreach from new management services organizations, health plans and risk bearing organizations. When evaluating a new market, we consider three primary factors:

1.the penetration and growth of Medicare Advantage and other value-based reimbursement models;

2.the presence of value-based primary care groups with whom we can partner to generate referrals and manage outcomes; and

3.how well oncology spend is currently managed in that market.

We believe that new markets we are focused on meet all of the above criteria and could provide us with significant opportunity to create value for patients, providers and payors.

We have multiple strategies we believe can achieve long term growth.

•Existing Market Contract Growth: Continue driving covered lives growth. Significant growth potential in existing markets can be achieved through expanding the scope of our services with existing partners and securing new contracts with new payors and independent practices. The addition of new de novo clinics and affiliated providers can drive additional growth. By continuing to build regional density in existing markets, we also have an opportunity to achieve efficiencies with increased scale.

•New Market Contract Growth: Our replicable operating model enables quick scaling in new markets. Oncology continues to be a key focus area for payors and providers, who are highly supportive of our entry into new markets. Our high priority markets have attractive market dynamics due to the high cost of oncology care in these geographies, the prevalence of risk-bearing organizations, and the presence of national payor partners with whom we collaborate in existing markets. Our fully delegated model provides a highly capital-efficient and scalable new market entry strategy, allowing us to leverage existing provider infrastructure in a market, while over time selectively building a presence of TOI PC clinics that allows us to support the mission of affordable, high-quality, and accessible oncology care in these geographies, while improving commercial performance in these populations, supporting the goals of both TOI and our payor partners.

•M&A Opportunities: Leveraging our existing pipeline and mergers and acquisition expertise can help us facilitate growth in both existing and new markets, allowing us to rapidly establish market presence. Once on-boarded, we can transition the affiliated practice to our value-based model, as well as expand and enhance the scope of services provided to patients by the affiliated practice, such as adding specialty pharmacy operations, managing clinical trials and access to our broad purchasing contracts. Independent oncologists continue to face a multitude of challenges and our acquisition model offers a path for these oncologists to continue to practice in their community without the burdens of business building or administration, while at the same time working alongside a dynamic and growing organization at the forefront of value-based care. We look for acquisition targets where the practice is philosophically aligned with us in driving the shift to value-based care, and our fully delegated model and network providers offer a direct perspective and line of communication with potential acquisition targets, particularly as we understand clinical practices, referral patterns, and market share in new geographies.

•Service Expansion: We can broaden scope and diversify service offerings, including ancillary and adjacent services focused on patient care and innovation and providing access to new oncology treatments being investigated in clinical trials that our affiliated practices manage. We have the potential to scale significantly faster with additional capital via

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new oncologist on-boarding and training, further technology investments, investments in ancillaries, and strategic acquisitions.

Contracting Overview

At a time when many FFS healthcare organizations have been struggling due to the decrease in service volumes, our value-based capitation payments have allowed us to maintain our level of member care and prioritize member safety by incentivizing the provision of care in the most appropriate setting.

We have focused our business on capitation arrangements and other types of value-based contracts, which we believe align provider incentives with both quality and efficiency of care. Under capitation arrangements, payors pay a fixed per member per month, or PMPM, amount for every plan member within a population assigned to us for oncology care.

Our affiliated providers are responsible for managing oncology care for this population based on a scope of medical services and drugs agreed upon by both parties. The PMPM rates for our capitation arrangements are determined based on our analysis of historical patient data and agreements with contractual partners, typically utilizing multiple years of historical utilization data, which we then analyze on a detailed basis using cancer diagnosis prevalence, disease state mix, site of care, therapeutic mix, treatment frequency and duration, and other medical economic analytics that allow us to take prudent and appropriate risk on the cost of care for a given patient population.

Where we are entering capitation contracts under our fully delegated model, we are also committing to providing traditional managed care administrative services, including i) network administration; ii) claims adjudication; and iii) utilization management.

In addition to capitation-based arrangements, we continue to explore several other forms of value-based arrangements. Although many of these arrangements continue to be based on a FFS-based methodology, our affiliated providers are eligible to earn additional bonuses based on their ability to achieve oncology specific clinical and other quality of care based benchmarks. While these alternative value-based arrangements may not produce as much initial revenue on a PMPM basis as capitation, we believe this flexibility in contracting models will allow us to speed our expansion into new markets while preserving the value-based economics that are critical for our business’ growth and success.

Payor Relationships

Our ability to consistently attract patients across multiple geographic markets depends on our ability to contract with payors in each market. Depending on the market, payors can be delegated medical groups who are taking risk or insurance companies themselves. By opening clinics in locations where the TOI PCs currently manage the oncology care for a large number of insured Medicare, commercial and Medicaid members, we believe we are creating net benefits for payors, as our affiliated providers are able to reduce unnecessary costs and improve patient care and experience. This also allows us to benefit from the value-based offerings already established by payors in the market, therefore not requiring us to single-handedly drive patient growth. Some of the biggest and most respected names in healthcare contract with the TOI PCs to provide oncology care to their members, including Anthem, CareMore Health, Heritage Provider Network and Optum Care. More than half of our revenue in 2025 was generated from value-based contracts where payors have made our affiliated providers their preferred or exclusive oncology group.

While our relationships with payors are long-standing, we believe we have limited concentration risk as our largest customer by revenue in 2025 represented approximately 14% of our patient services revenue.

Provider and Clinic Capacity Growth

Our primary driver for growth in provider and clinic capacity is to create network adequacy to service members from payors with whom we have capitated or other value-based arrangements. For each market we currently operate in or are considering entering, we do a detailed assessment of the existing market landscape and determine the optimal approach to create the capacity we need given our payor relationships and pipeline of contracts. We can achieve capacity growth through multiple avenues, including practice acquisitions, construction of de novo clinics, and the deployment of independent oncology clinics via a managed network. Practice acquisitions offer an opportunity to gain scale and market presence rapidly, de novo clinics allow us to build out our network in more cost-effective manner than a mature practice acquisition, and finally the deployment of network providers removes the need for any capital deployment for TOI, but is also the least controllable site of care, so must be balanced with TOI PC clinics to optimize contract performance and risk management. We refer to this mix of captive and network practices as TOI's "hybrid model," and believe this balanced approach to patient access can work in tandem to achieve optimal scale, network presence, and speed to market.

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We also believe we have built a robust and data-driven approach to acquisitions, with a dedicated team to identify, assess and integrate physician practices into our affiliated and independent network, and a strong pipeline of targets in both existing and new markets.

Clinic Structure, Staffing and Network Design

We have a standard clinic design and approach to staffing that has been refined over many years. Managed clinics typically range from 2,000 to 3,000 square feet with 3-4 providers (physicians and advanced practice providers) per clinic. We have flexibility around clinic size to allow us to establish smaller clinics and part time staffing in areas where needed to ensure the TOI PCs can meet network adequacy under existing payor contracts. We group our managed clinics in a similar geographic area into pods, with multiple pods in each market. We have operations teams managing our markets and pods allowing us to drive performance and scale efficiently.

Competition

The U.S. healthcare industry is generally highly competitive. We compete with large and medium-sized local and national providers of cancer care services, such as health system affiliated practices, for, among other things, contracts with payors, recruitment of physicians and other medical and non-medical personnel and patients. The closest competitors are traditional oncology physician practices, such as American Oncology Network, Inc., U.S. Oncology Network, Inc., and OneOncology, Inc. These organizations are predominantly reimbursed via FFS contracts, which we believe can often lead to over-utilization of treatments that may be medically appropriate but often results in higher costs. Secondary competitors may include specialty benefit managers. These include companies such as Evolent Health, Thyme Care, and OncoHealth. These benefit managers seek to change provider or patient behavior by reviewing and authorizing treatment requests or guiding patients towards lower-cost sites of care. The benefit manager model can produce incremental improvement in utilization, but the benefit managers are often unable to achieve results comparable to managed healthcare practices like ours due to the lack of ability to directly influence physician behavior or control referrals. Furthermore, the benefit manager model frequently results in an antagonistic relationship with physicians who are operating in a traditional FFS-based practice that is not designed around value-based pathways. We distinguish ourselves from other managed oncology practices and specialty benefit managers in our ability to deploy this hybrid model to align incentives across the care continuum, including physicians and payors in delivering high quality care at lower costs, and we believe there are currently no other value-based oncology management companies of meaningful scale in the U.S. offering such a vertically and horizontally integrated approach.

We believe the principal competitive factors for serving the healthcare market for Medicare beneficiaries include: patient experience, quality of care, health outcomes, total cost of care, brand identity and trust in that brand. We believe we compete favorably on all these factors.

Government Regulation

Regulatory Licensing, Accreditation and Certification

Many states, including California, require regulatory approval, including licensure, accreditation and certification before establishing certain types of clinics offering certain professional and ancillary services, including the services we offer. The operations of our managed clinics are subject to extensive federal, state and local regulation relating to, among other things, the adequacy of medical care, equipment, personnel, operating policies and procedures, dispensing of prescription drugs, fire prevention, rate-setting and compliance with building codes and environmental protection. Our ability to operate profitably will depend in part on the ability of our managed clinics and doctors to obtain and maintain all necessary licenses, accreditation and other approvals, and maintain updates to their enrollment in the Medicare and Medicaid programs, including the addition of new clinic locations, providers and other enrollment information. In addition, certain ancillary services such as the provision of diagnostic laboratory testing require additional state and federal licensure and regulatory oversight, including oversight by CMS, under Clinical Laboratory Improvement Amendments of 1988, which requires all clinical laboratories to meet certain quality assurance, quality control and personnel standards, and comparable state laboratory licensing authorities, including for example, the California Department of Public Health. Our specialty pharmacy operations must also comply with applicable laws. Sanctions for failure to comply with applicable state and federal licensing, accreditation, certification and other regulatory requirements include suspension, revocation or limitation of the applicable authorization, significant fines and penalties and/or an inability to receive reimbursement from government healthcare programs and other third-party payors.

State Regulations and Corporate Practice of Medicine and Fee-Splitting Laws

Our arrangements with the TOI PCs are subject to various state laws, including California, commonly referred to as corporate practice of medicine and fee-splitting laws, which are intended to prevent unlicensed persons from interfering with or influencing the physician’s professional judgment, and prohibiting the sharing of professional service fees with non-

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professional or business interests. These laws vary from state to state and are subject to broad interpretation and enforcement by state regulators. A determination of non-compliance against us and/or the TOI PCs could lead to adverse judicial or administrative action, civil or criminal penalties, receipt of cease and desist orders from state regulators, loss of provider licenses, and/or restructuring of these arrangements.

Certain state healthcare regulations also introduce additional reporting and compliance requirements that may adversely affect our ability to enter into strategic transactions or execute material contracts. In California, California Assembly Bill 1415 (“AB 1415”), signed into law on October 11, 2025 and effective January 1, 2026, expanded the authority of the California Office of Health Care Affordability (“OHCA”) over health care entities and designated noticing entities, including management services organizations. Under AB 1415, healthcare entities, noticing entities and other designated entities must provide at least 90 days’ written notice before closing certain material transactions, including any sale or transfer of a material amount of assets or a change of control. After reviewing the information provided in the notice, OHCA has the right to conduct a more thorough cost and market impact review (“CMIR”), which could delay a transaction closing by several months. To the extent that our management services agreements or any corporate transaction involving our California operations is deemed a material transaction subject to OHCA’s jurisdiction, we could face a lengthy notice period and may be subject to a CMIR that could materially delay or impair our ability to consummate strategic transactions, enter into new business arrangements or execute on our growth strategy. AB 1415 also grants OHCA authority to impose data reporting requirements on management services organizations, the full scope of which remains subject to further rulemaking and regulatory guidance. Regulations to implement AB 1415 are expected in Spring 2026, and we cannot predict with certainty how OHCA will exercise its expanded authority in such regulations or whether future legislative or regulatory developments will further expand the transactions or entities subject to reporting requirements.

Healthcare Fraud and Abuse Laws

We are subject to a number of federal and state healthcare regulatory laws that restrict certain business practices in the healthcare industry. These laws include, but are not limited to, federal and state anti- kickback, false claims, self-referral and other healthcare fraud and abuse laws.

The federal Anti-Kickback Statute, or AKS, prohibits, among other things, knowingly and willfully offering, paying, soliciting or receiving remuneration, directly or indirectly, in cash or kind, to induce or reward either the referral of an individual for, or the purchase, order or recommendation of, any good or service, for which payment may be made under federal and state healthcare programs such as Medicare and Medicaid. A person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation. The AKS includes statutory exceptions and regulatory safe harbors that protect certain arrangements. The AKS safe harbors for value-based arrangements require, among other things, that the arrangement does not induce a person or entity to reduce or limit medically necessary items or services furnished to any patient. Failure to meet the requirements of the safe harbor, however, does not render an arrangement illegal. Rather, the government may evaluate such arrangements on a case-by-case basis, taking into account all facts and circumstances, including the parties’ intent and the arrangement’s potential for abuse, and may be subject to greater scrutiny by enforcement agencies.

The Stark Law prohibits a physician who has a financial relationship, or who has an immediate family member who has a financial relationship, with entities providing Designated Health Services, or DHS, from referring Medicare and Medicaid patients to such entities for the furnishing of DHS, unless an exception applies. The Stark Law also prohibits the entity from billing for any such prohibited referral. Unlike the AKS, the Stark Law is violated if the financial arrangement does not meet an applicable exception, regardless of any intent by the parties to induce or reward referrals or the reasons for the financial relationship and the referral.

The Federal False Claims Act, or FCA, prohibits a person from knowingly presenting, or caused to be presented, a false or fraudulent request for payment from the federal government, or from making a false statement or using a false record to have a claim approved. The FCA further provides that a lawsuit thereunder may be initiated in the name of the United States by an individual, a “whistleblower,” who is an original source of the allegations. Moreover, the government may assert that a claim including items and services resulting from a violation of the AKS or the Stark Law constitutes a false or fraudulent claim for purposes of the civil False Claims Act. Penalties for a violation of the FCA include fines for each false claim, plus up to three times the amount of damages caused by each false claim.

Further, the Civil Monetary Penalties Statute authorizes the imposition of civil monetary penalties, assessments and exclusion against an individual or entity based on a variety of prohibited conduct, including, but not limited to offering remuneration to a federal health care program beneficiary that the individual or entity knows or should know is likely to influence the beneficiary to order or receive health care items or services from a particular provider.

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Health Insurance Portability and Accountability Act of 1996 ("HIPAA") also established federal criminal statutes that prohibit, among other things, knowingly and willfully executing, or attempting to execute, a scheme to defraud any healthcare benefit program, including private third-party payors, and knowingly and willfully falsifying, concealing or covering up a material fact or making any materially false, fictitious or fraudulent statement in connection with the delivery of or payment for healthcare benefits, items or services. Similar to the AKS, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation.

Several states in which we operate have also adopted similar fraud and abuse laws as described above. The scope of these laws and the interpretations of them vary from state to state and are enforced by state courts and regulatory authorities, each with broad discretion. Some state fraud and abuse laws apply to items or services reimbursed by any payor, including patients and commercial insurers, not just those reimbursed by a federally funded healthcare program, including California's anti-kickback statutes and the Physician Ownership and Referral Act of 1993.

Violation of any of these laws or any other governmental regulations that apply may result in significant penalties, including, without limitation, administrative civil and criminal penalties, damages, disgorgement, fines, additional reporting requirements and compliance oversight obligations, contractual damages, the curtailment or restructuring of operations, exclusion from participation in governmental healthcare programs and/ or imprisonment.

Healthcare Reform

In the United States, there have been, and we expect there will continue to be, a number of legislative and regulatory changes to the healthcare system, many of which are intended to contain or reduce healthcare costs. By way of example, in the United States, the Affordable Care Act (“ACA”), substantially changed the way healthcare is financed by both governmental and private insurers. Since its enactment, there have been judicial, executive and Congressional challenges to certain aspects of the ACA. On June 17, 2021, the U.S. Supreme Court dismissed the most recent judicial challenge to the ACA without specifically ruling on the constitutionality of the ACA. However, the ACA continues to face uncertainty. The Trump administration has signaled its intent to revisit certain ACA policies and has taken executive actions affecting the law's implementation. Among other things, the administration has reduced funding for ACA marketplace outreach and navigator programs, shortened open enrollment periods, increased the availability of high-deductible/catastrophic plans, and opposed extending enhanced premium tax credits aimed at reducing premium costs. It is unclear how other healthcare reform measures of the Trump administration or other efforts, if any, to challenge, repeal or replace the ACA will impact the ACA or our business.

In addition, other legislative changes have been proposed and adopted since the ACA was enacted. These changes included aggregate reductions to Medicare payments to providers of 2% per fiscal year, which went into effect on April 1, 2013 and, due to subsequent legislative amendments to the statute, will remain in effect through 2030, with the exception of a temporary suspension from May 1, 2020 through March 31, 2022 and a 1% payment reduction from April 1, 2022 to June 30, 2022, unless additional Congressional action is taken. In addition, on January 2, 2013, the American Taxpayer Relief Act of 2012 was signed into law, which, among other things, reduced Medicare payments to several providers, including hospitals, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years.

CMS, through the Centers for Medicare and Medicaid Innovation, or CMMI, has implemented or has announced plans to implement numerous demonstration models designed to test value-based reimbursement models, some of which are specifically focused on oncology services. For example, in 2016, CMS initiated the Oncology Care Model demonstration, which continued throughout 2023, and provides participating physician practices, including the TOI PCs that participate in this program, with performance-based financial incentives that aim to manage or reduce Medicare costs without negatively affecting the efficacy of care. In late 2019, CMS issued a request for information on the Oncology Care First model, a new voluntary model that, if implemented, would build on the Oncology Care Model. More recently, CMMI has announced plans to implement the Radiation Oncology Model, which would require radiotherapy providers in certain regions to participate in a prospective, episode-based payments model where payment is based on a patient’s diagnosis as opposed to the traditional volume-based FFS payment model. Although the Radiation Oncology Model was originally intended to begin on January 1, 2022, legislation delayed its implementation until July 1, 2023 and therefore, the impact of this new model has yet to determined. There likely will continue to be regulatory proposals directed at containing or lowering the cost of healthcare. The implementation of cost containment measures or other healthcare reforms may prevent us from being able to generate revenue or attain growth, any of which could have a material impact on our business.

The Trump Administration has also recently taken actions intended to reduce the cost of prescription drugs, including drugs purchased directly by consumers. The administration issued two Executive Orders aimed at lowering drug prices through multiple directives, including directives to government agencies and officials to identify most-favored-nation pricing targets for prescription drugs (and looking to pharmaceutical manufacturers to make significant progress towards delivering target prices to patients), to facilitate direct-to-consumer purchasing programs for pharmaceutical manufacturers to sell their products to

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patients at the most-favored-nation price, to enhance competition for high-cost prescription drugs by accelerating approval of generics and biosimilars, facilitating the process for re-classifying prescription drugs as OTC drugs, and increasing drug importation. In the wake of the Executive Orders and related executive initiatives, a number of pharmaceutical manufacturers have announced new or expanded direct-to-consumer offerings with discounted prices and/or reached agreement with the federal government regarding discounted pricing for drugs, including prices for Medicaid drugs and newly launched products. TrumpRx, a website sponsored by the federal government that offers pharmaceutical direct-to-consumer channels, also launched in February 2026. Federal agencies are also developing and proposing new drug pricing and payment pilot programs based on international pricing metrics under Medicare Parts B and D as well as Medicaid. Other healthcare reform efforts or actions under the Trump Administration may affect prescription drug pricing, access to healthcare coverage or the funding of health care benefits, although the full impact of such efforts or actions cannot be predicted. For example, Congressional Budget Office has estimated that Medicaid provisions in the 2025 budget reconciliation legislation, including restrictions in eligibility and funding for Medicaid, as well as changes to the healthcare marketplace, will increase the number of uninsured.

Further, healthcare providers and industry participants are also subject to a growing number of requirements intended to promote the interoperability and exchange of patient health information. For example, on April 5, 2021, healthcare providers and certain other entities became subject to information blocking restrictions pursuant to the Cures Act that prohibit practices that are likely to interfere with the access, exchange or use of electronic health information ("EHI"), except as required by law or specified by HHS as a reasonable and necessary activity.

Violations may result in penalties or other disincentives. It is unclear at this time what the costs of compliance with the new rules will be, and what additional risks there may be to our business.

Federal and State Insurance and Managed Care Laws

Regulation of downstream risk-sharing arrangements, including, but not limited to, global risk and other value-based arrangements, varies significantly from state to state. Some states require downstream entities and Risk Bearing Organization ("RBOs") to obtain an insurance license, a certificate of authority, or an equivalent authorization, in order to participate in downstream risk-sharing arrangements with payors. In some states, statutes, regulations and/or formal guidance explicitly address whether and in what manner the state regulates the transfer of risk by a payor to a downstream entity. However, the majority of states do not explicitly address the issue, and in such states, regulators may nonetheless interpret statutes and regulations to regulate such activity. If downstream risk-sharing arrangements are not regulated directly in a particular state, the state regulatory agency may nonetheless require oversight by the licensed payor as the party to such a downstream risk-sharing arrangement. Such oversight is accomplished via contract and may include the imposition of reserve requirements, as well as reporting obligations. Further, state regulatory stances regarding downstream risk-sharing arrangements can change rapidly and codified provisions may not keep pace with evolving risk-sharing mechanisms and other new value-based reimbursement models. Certain of the states where we currently operate or may choose to operate in the future regulate the operations and financial condition of RBOs like us and our affiliated providers. These regulations can include capital requirements, licensing or certification, governance controls and other similar matters. While these regulations have not had a material impact on our business to date, as we continue to expand, these rules may require additional resources and capitalization and add complexity to our business.

Privacy and Security

Numerous state, federal and foreign laws, including consumer protection laws and regulations, govern the collection, dissemination, use, access to, confidentiality and security of personal information, including health-related information. In the United States, numerous federal and state laws and regulations, including data breach notification laws, health information privacy and security laws, including HIPAA, and federal and state consumer protection laws and regulations (e.g., Section 5 of the Federal Trade Commission ("FTC") Act, that govern the collection, use, disclosure, and protection of health-related and other personal information could apply to our operations or the operations of the TOI PCs.

In addition, certain state laws, such as the California Consumer Privacy Act, or the CCPA and the California Privacy Rights Act of 2020, or the CPRA, govern the privacy and security of personal information, including health-related information in certain circumstances, some of which are more stringent than HIPAA and many of which differ from each other in significant ways and may not have the same effect, thus complicating compliance efforts. Failure to comply with these laws, where applicable, can result in the imposition of significant civil and/or criminal penalties and private litigation. Privacy and security laws, regulations, and other obligations are constantly evolving, may conflict with each other to complicate compliance efforts, and can result in investigations, proceedings, or actions that lead to significant civil and/or criminal penalties and restrictions on data processing.

Intellectual Property

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At present, we own no material intellectual property.

Insurance

We maintain insurance, excess coverage, or reinsurance for property and general liability, professional liability, directors’ and officers’ liability, workers’ compensation, cybersecurity and other coverage in amounts and on terms deemed adequate by management, based on our actual claims experience and expectations for future claims. Future claims could, however, exceed our applicable insurance coverage.

Employees and Human Capital Resources

As of December 31, 2025, we and TOI PCs collectively had approximately 641 employees, including approximately 116 oncologists and advanced practice providers. We consider our relationship with our employees to be good. None of our employees are represented by a labor union or party to a collective bargaining agreement.

Our goal is to provide top quality oncology care to our patients, and we view our human capital-related initiatives as essential to continuing to reach that goal. Such initiatives include: (i) implementing a robust talent acquisition approach, including through competitive pay and benefits, (ii) implementing programs to promote diversity and foster a sense of connection and community throughout our company, (iii) offering an array of opportunities for learning and development opportunities, and (iv) conducting annual employee engagement surveys and developing action plans based on the survey outcomes.

Availability of Information

We were originally incorporated in Delaware on November 19, 2019 as a special purpose acquisition company (f/k/a DFP Healthcare Acquisition Corp.). In November 2021, we consummated our business combination with TOI Parent, Inc. (the “Business Combination”). In connection with the closing of the Business Combination, TOI Parent, Inc. became our wholly owned subsidiary and we changed our name to The Oncology Institute, Inc. We file or furnish annual, quarterly and current reports, proxy statements and other documents with the Securities and Exchange Commission (the “SEC”) under the Securities Exchange Act of 1934 (as amended, the "Exchange Act"). The SEC maintains an internet website at www.sec.gov that contains reports, proxy and information statements and other information regarding issuers, including us, that file electronically with the SEC.

We also make available free of charge through our website, https://investors.theoncologyinstitute.com/, electronic copies of certain documents that we file with the SEC, including our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. Information on our website or any other website is not incorporated by reference into, and does not constitute a part of, this Annual Report.