Contents

• Introduction
• Medicare Hospital Insurance Financing
• What Is the HI Trust Fund?
• HI and SMI Trust Funds Jointly Finance Part C
• History of HI Trust Fund Solvency Projections
• Current Insolvency Projections
• Historical Projections
• Future Projections
• Alternative Projections
• What Would Happen If the HI Trust Fund Became Insolvent?
• Medicare Financing Issues and Considerations for Congress

Summary

Medicare, the federal health insurance program that pays for covered health services for enrolled beneficiaries, provided coverage to approximately 70.7 million beneficiaries in 2026 and incurred total expenditures of approximately $1.33 trillion, of which $481 billion was paid by Part A. Part A, also known as Hospital Insurance (HI), covers primarily inpatient care at health facilities such as hospitals and skilled nursing facilities. Part A is financed by the HI Trust Fund, which is funded mostly by payroll taxes, taxes on Social Security benefits, and accumulated trust fund assets.

The 2026 Medicare Trustees Report projects that Medicare Part A expenditures will continue to grow during the next 10 years, primarily because of increases in the number of beneficiaries and the volume and intensity of health services.

The Medicare trustees report notes that since the inception of Medicare in 1966, the HI trust fund has always faced a projected shortfall. If the trust fund runs out of money, it would become insolvent. The HI insolvency date has been postponed several times through legislative changes that, for example, have had the effect of restraining growth in program spending. The 2026 trustees report projects that the HI trust fund will transition from a surplus in 2026 to a deficit in 2027. HI is projected to spend down accumulated assets until the trust fund becomes insolvent in 2033, the same year of insolvency as estimated by the trustees in 2025.

There are no provisions in Medicare's authorizing legislation that specify what would happen if insolvency were to occur. In the event of insolvency, policymakers may face decisions regarding increasing revenues, decreasing expenditures, incurring additional debt, or some combination thereof.

The Supplementary Medical Insurance (SMI) trust fund, which finances Medicare Parts B and D, is funded primarily through beneficiary premiums and transfers from the general fund of the Treasury. Unlike the HI trust fund, the SMI trust fund's financing is updated automatically each year to cover projected expenditures and therefore is not subject to the same solvency concerns. A continuing shift from providing care in inpatient (Part A) settings to outpatient (Parts B and D) settings has resulted in a greater portion of Medicare spending being covered by beneficiary premiums and general revenues than by dedicated payroll taxes. This shift suggests beneficiaries face increased premiums for Parts B and D in the years ahead.

This report describes how the Medicare program is financed, the sources of funding for the program, and the role of trust funds in the financing structure. It also summarizes the history of the trust funds, projections of Part A spending and revenue, and the factors contributing to projected Medicare spending growth, including enrollment growth, inflation, and health care utilization. It reviews historical and future projections of Medicare spending and solvency, based on the annual reports of the Medicare trustees from 1997 to 2026, and alternative projections presented by the trustees. These projections illustrate the long-term financing challenges facing the Medicare program and provide a framework for evaluating potential policy options for adjusting Medicare revenues, expenditures, and trust fund solvency.

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Introduction

Medicare is a federal insurance program that pays for covered health care services of qualified beneficiaries. It was established in 1965 under Title XVIII of the Social Security Act as a federal entitlement program to provide health insurance to individuals aged 65 and older, and it has been expanded over the years to include permanently disabled individuals under the age of 65.

Medicare consists of four distinct components: Parts A through D. Part A covers hospital services, skilled nursing facility (SNF) services, home health visits, and hospice services. Most persons aged 65 and older are automatically entitled to premium-free Part A because they or their spouse paid payroll taxes for at least 40 quarters (10 years) on earnings covered by either the Social Security or the Railroad Retirement systems. Part B covers a broad range of medical services, including physician services, laboratory services, durable medical equipment, and outpatient hospital services. Enrollment in Part B is voluntary; however, most beneficiaries with Part A also enroll in Part B. Part C, Medicare Advantage (MA), provides options to enroll in plans offered by private health insurance companies, such as managed care plans, for beneficiaries who are enrolled in both Part A and Part B. Part D provides optional outpatient prescription drug coverage.¹

Medicare expenditures are driven by a variety of factors, including the level of enrollment, provider payment rates, the quantity and complexity of medical services provided, health care inflation, and life expectancy. In 2026, Medicare provided benefits to about 70.7 million persons at an estimated total cost of $1.33 trillion, of which $481 billion was paid by Part A.²

The Medicare program has two separate trust funds, the Hospital Insurance (HI) trust fund and the Supplementary Medical Insurance (SMI) Trust fund. The Part A program, which is financed mainly through payroll taxes levied on current workers, is accounted for through the HI trust fund. The Part B and Part D programs, which are funded primarily through general revenue and beneficiary premiums, are accounted for through the SMI trust fund.³ Both funds are maintained by the Department of the Treasury and overseen by the Medicare Board of Trustees, which reports annually to Congress concerning the funds' financial status.⁴ Financial projections are made using economic assumptions based on current law, including estimates of consumer price index, workforce size, wage increases, and life expectancy.

From its inception, the HI trust fund has faced a projected shortfall and eventual insolvency. General revenue and premium levels automatically adjust to finance projected SMI spending on Part B and Part D. Because of the way it is financed, the SMI trust fund is unlikely to become insolvent; however, the Medicare trustees have continued to express concerns about the rapid growth in SMI costs.⁵

Medicare Hospital Insurance Financing

Similar to the Social Security program, the HI portion of Medicare was designed to be financed through dedicated sources of income, rather than by relying on general tax revenues. The primary source of income credited to the HI trust fund is payroll taxes, which provided 87% of income to the trust fund in 2025. Medicare payroll taxes are paid by employees and employers; each pays a tax of 1.45% on earnings. The self-employed pay 2.9%. Unlike Social Security, there is no upper limit on earnings subject to the tax.⁶ The Patient Protection and Affordable Care Act (ACA; P.L. 111-148, as amended) imposed an additional tax of 0.9% on workers' wages that exceed $200,000 for single filers and $250,000 for joint filers, effective for taxable years beginning in 2013.⁷

Additional income to the HI trust fund consists of premiums paid by enrollees who are not entitled to premium-free Medicare Part A through their (or their spouse's) work in covered employment, a portion of the federal income taxes paid on Social Security benefits,⁸ and interest on federal securities held by the HI trust fund.

What Is the HI Trust Fund?

The HI trust fund is a financial account in the U.S. Treasury into which all income to the Part A portion of the Medicare program is credited and from which all benefits and associated administrative costs of the Part A program are paid.⁹

HI operates on a "pay-as-you-go" basis, meaning the annual revenues to the HI trust fund, primarily the taxes paid by current workers and their employers, are used to pay Part A benefits for today's Medicare beneficiaries. When the government receives Medicare revenues (e.g., payroll taxes), income is credited by the Treasury to the appropriate trust fund in the form of special issue interest-bearing government debt securities.¹⁰ Interest on these securities is also credited to the trust fund in the form of additional securities. In other words, the trust fund balance is held in the form of Treasury securities rather than in cash. The tax income exchanged for these securities then goes into the general fund of the Treasury and is indistinguishable from other cash in the general fund; this cash may be used for any government spending purpose. When payments for Medicare Part A services are made, the payments are paid out of the general fund of the Treasury and a corresponding amount of securities is deleted from (written off) the HI trust fund.

In years in which the HI trust fund spends less than it receives in income, the fund has a surplus. When this occurs, the HI trust fund securities exchanged for any income in excess of spending show up as assets on the trust fund's financial accounting balance sheets and are available to the system to meet future obligations. The trust fund surpluses are not reserved for future Medicare benefits but are simply bookkeeping entries that indicate how much Medicare has lent to the Treasury (or, alternatively, what is owed to Medicare by the Treasury). From a unified budget perspective, these assets of the trust fund are offset by liabilities to the general fund of the Treasury because they represent future budget obligations.¹¹

If, in a given year, the HI trust fund spends more than it receives in income, the fund has a deficit. In deficit years, Medicare can redeem any government securities accumulated in previous years (including interest). When the securities are redeemed, the government must raise the resources necessary to pay for the securities and the monies are transferred from the Treasury's general fund to the HI trust fund. Should the assets credited to the trust fund reach zero, the fund would be deemed insolvent. (See Appendix A for a discussion of recent and projected HI balances and for data on historical and projected HI operations through 2035.)

HI and SMI Trust Funds Jointly Finance Part C

Medicare Advantage (Part C) does not have its own trust fund. Instead, MA is financed by the HI and SMI trust funds. Medicare pays private health plans monthly capitated (a set amount of money paid upfront) per person payments to provide the equivalent of Part A and Part B coverage to beneficiaries enrolled in MA. These MA payments are drawn in appropriate percentages from the HI and SMI trust funds based on the Centers for Medicare & Medicaid Services (CMS) estimates of spending for Part A and Part B services. In 2025, 39.5% of MA payments were drawn from the HI trust fund and 60.5% were drawn from the SMI trust fund.¹² Medicare Part D benefits offered through Medicare Advantage prescription drug plans are financed separately through the SMI Trust Fund's Part D account.

History of HI Trust Fund Solvency Projections

The HI trust fund has never become insolvent. The Medicare Board of Trustees projected insolvency for the HI trust fund beginning with the 1970 report, at which time the trust fund was expected to become insolvent in two years. The insolvency date has been postponed a number of times since the beginning of Medicare through various methods (see Figure 1 and Table 1). For example, Congress has occasionally adjusted the payroll tax rate to maintain the financial adequacy of the HI trust fund, such as the increase in the payroll tax that was enacted in 1982. Other legislative changes also have been made at various times to slow the growth in HI program spending; generally, these measures have been part of larger budget reconciliation laws that attempted to restrain overall federal spending. See Appendix B for historical payroll tax rates and Appendix C for an overview of legislative, economic, and methodological changes that affected 1997-2026 insolvency projections.

Figure 1. Projected Number of Years Until Medicare HI Trust Fund Insolvency and Selected Laws with Impact on Insolvency Date

Sources: Intermediate projections of various Medicare trustees reports, 1978-2026. Note: No specific estimates were provided by the Medicare trustees for 1989. Many laws have affected solvency. The four laws labeled in Figure 2 are shown because they resulted in large changes to the solvency date.

Current Insolvency Projections

In their 2026 report,¹³ the Medicare trustees project that the HI trust fund will become insolvent in 2033, the same year as in their 2025 report. Within 2033, insolvency is projected to occur during the second quarter. The trustees attribute the consistency of their current 2033 insolvency date estimate with that in last year's report to higher Medicare Advantage enrollment and spending that was mostly offset by lower Part A spending in the 2025 base year of the projections.

Historical Projections

Starting in 2008, expenditures in the HI trust fund exceeded income each year through 2015. Although the Medicare trustees reported small surpluses in 2016 and 2017, the HI trust fund again experienced deficits in 2018 and 2019 (see Table A-1). In 2020, the HI trust fund experienced a larger deficit, primarily due to accelerated and advance payments made to health care providers during the COVID-19 public health emergency.¹⁴ Providers who received these accelerated and advance payments would have fulfilled these obligations and offset these payments in 2021-2023, resulting in HI trust fund surpluses in those years. In 2024, there was a surplus of $28.7 billion, partly driven by an increase in payroll tax revenue, and the trustees projected insolvency date moved out to 2036. The 2025 surplus dropped to $18.2 billion, with the decrease driven by higher enrollment and spending.

Future Projections

The 2026 trustees report projects that 2026 will be the last year of surpluses. In 2027 and in all following years, the trustees project deficits until the HI trust fund becomes depleted (insolvent) in 2033 (see Figure 2).

Figure 2. HI Trust Fund Assets at Beginning of Year as a Percentage of Annual Expenditures (estimates from selected 2009-2026 Medicare trustees reports)

Sources: Data from the Boards of Trustees, Federal Hospital Insurance and Federal Supplementary Medical Insurance Trust Funds, 2009 and 2025 Annual Report of the Boards of Trustees of the Federal Hospital Insurance and the Federal Supplementary Medical Insurance Trust Funds, Table II.E1 (2009), Supplementary Tables (2024-2025), and summaries of the applicable 2011 through 2021 Annual Reports of the Social Security and Medicare Boards of Trustees, Chart D (2011) and Chart E (2013, 2015-2021).

Alternative Projections

Each year, beginning in 2010, the CMS actuaries have issued an illustrative alternative scenario that assumes certain ACA changes that reduce Part A provider payments would be phased out gradually.¹⁵ The ACA linked these provider payment reductions to economy-wide productivity growth. Because the differences in assumptions between current law and the alternative scenario are phased in from 2028 to 2042, and therefore have little impact until after 2030, the alternative scenario projects the same 2033 year of HI insolvency as the current law scenario. With the phaseout of the productivity adjustments, the alternative scenario projects a higher spending trajectory that diverges from the trustees' projections under current law from 2028 to 2100.

What Would Happen If the HI Trust Fund Became Insolvent?

A practical function of the HI trust fund is to permit the continued payment of bills in the event of a temporary financial strain (e.g., lower income or higher costs than expected) without requiring legislative action or curtailing health care delivery. As long as the HI trust fund has a balance (i.e., securities are credited to the fund), the Treasury Department is authorized to make payments for Medicare Part A services. If the HI trust fund cannot pay all current expenses out of current income and accumulated trust fund assets, the HI trust fund would be considered insolvent.¹⁶

To date, the HI trust fund has never become insolvent. There are no provisions in the Social Security Act that govern what would happen if insolvency were to occur. For example, the program has no statutory authority to use general revenues to fund Part A services in the event of such a shortfall, and agencies may not transfer funds unless authorized to do so by Congress.¹⁷

In their 2026 report, the Medicare trustees project that the HI trust fund will be exhausted in 2033. At that time, there will no longer be sufficient funds to fully cover Part A expenditures. Although the trust fund would continue to receive tax and other income, those funds, according to the trustees, would cover 89% of Part A expenses. The Medicare trustees have suggested that in the event of HI trust fund insolvency, there could initially be delays in payments to plans and providers.¹⁸ Following soon after insolvency, beneficiary access to Part A services could "rapidly be reduced."¹⁹ However, as the Social Security Act does not specify what would happen if the HI trust fund were to become insolvent, it is unclear what actions CMS might take under this circumstance.²⁰ CMS could choose to pay full benefits on a delayed schedule, although the length of the delay would grow as unpaid benefits from one period reduce the amount of money available to pay benefits for the next period. Alternatively, CMS could choose to make timely but reduced payments to plans and providers. Both options for operating after insolvency are legally untested and could potentially and quickly erode health providers' finances and beneficiaries' access to health care.²¹

Unless action is taken prior to the date of insolvency to increase revenues or to decrease expenditures, or some combination of the two, Congress may face a legislative decision regarding whether, and how, to provide for another source of funding or authorize the assumption of additional debt to make up for the HI trust fund deficits.

To make the HI trust fund solvent for the next 75 years beginning in 2026, the trustees estimate that payroll taxes would have to immediately increase by 0.56 percentage points or benefit spending would have to decrease by 12%.²² This 0.56 percentage-point payroll tax increase, to achieve solvency, is 0.16 percentage points higher than in the prior trustees report from 2025. This indicates a greater deficit for the HI trust fund during the next 75 years than previously projected. The trustees attribute this larger deficit in the 2026 report to higher spending in the 2025 base year of the projections, reduced taxation of Social Security benefits due to the FY2025 reconciliation law (P.L. 119-21), and lower projected fertility and immigration, which are estimated to reduce the number of wage-earning workers during the next 75 years.²³

Medicare Financing Issues and Considerations for Congress

Much of the concern about Medicare's financial status tends to focus on the HI trust fund date of insolvency, when Medicare would no longer have the resources to pay for Part A health care services in full. This focus can, however, detract from larger issues confronting the Medicare program as a whole and from the program's current and future impact on the federal budget and on taxpayers. When viewed from the perspective of the entire federal budget, as the number of beneficiaries and per capita health care costs continue to grow, total Medicare spending obligations (HI and SMI spending combined) are expected to place demands on a growing share of the federal budget. The Congressional Budget Office (CBO) projects that Medicare will increase from 17% of federal spending in FY2025 to 25% in FY2056.²⁴

Aging of the population and growth in the consumption of health care will likely contribute to the future risk of Medicare's insolvency and spending trajectory. Over the next 10 years, 2026-2035, the trustees project that Part A inflation-adjusted spending will grow primarily because of increases in the number of beneficiaries and the volume and intensity of health services.²⁵ Under current law, Medicare payment rates are projected to grow more slowly than the Consumer Price Index. New technologies, drugs, and patterns of care contribute to this growth in services. As the population has aged, the ratio of current workers to Medicare beneficiaries declined from 4.0 workers per beneficiary in 1980 to 2.7 workers per beneficiary in 2026. This ratio is projected to further decline to 2.4 in 2035.²⁶

Over the longer term in 2051-2100, the trustees project inflation to be the largest driver of Medicare spending growth, with Medicare prices projected to slightly lag behind the broader Consumer Price Index. After removing the effect of inflation, the volume and intensity of health services are the largest driver of spending. During this longer-term period, enrollment growth has a smaller impact, as population growth is projected to slow, although the trustees project that the ratio of current workers to Medicare beneficiaries will decline further to 2.0 in 2100.

As noted above, because of the way it is financed, the SMI (Parts B and D) portion of Medicare is unlikely to become insolvent. Yet—over time—a crucial underlying phenomenon is likely to challenge policymakers. That is, a continuing shift from providing care in inpatient (Part A) settings to outpatient (Parts B and D) settings has resulted in a greater portion of Medicare spending being covered by beneficiary premiums and general revenues than by dedicated payroll taxes.²⁷

In the future, the Medicare trustees estimate that the portion of total federal personal and corporate income tax revenue needed to fund SMI will increase from about 17.6% in 2025 to about 28.6% in 2040 and 38.3% in 2100.²⁸

Congress may face growing pressure to enact changes. The growth of enrollment and the lag of payment rates below inflation may create pressure on policymakers to increase Medicare spending. Meanwhile, the program's growing demands on the federal budget and approaching insolvency may increase pressure to reduce expenditures. A blend of policies could be considered to respond to these competing demands.

To prevent insolvency of Part A, Congress may choose to reduce spending, take on additional debt, or increase revenue. However, these options involve trade-offs. Reducing spending may lower payments to health providers and restrict beneficiaries' access to benefits and services. Increasing taxes or premiums may reduce economic growth and taxpayers' income. Policymakers have repeatedly tried to minimize negative impacts of spending reductions, such as by targeting fraud, low-value care, or empirically identified overpayments (for specific examples of such legislation, see Appendix C). Other reforms have changed payment methodologies in ways meant to encourage efficiency, such as prospectively bundling payments for a group of services rather than paying separately for each service. For further resources on Medicare payment and financing reforms, see CBO's Budget Options and the Medicare Payment Advisory Commission's reports to Congress on Medicare payment policy.²⁹

Appendix A. Operation of the Hospital Insurance Trust Fund

In 2004, Medicare Part A expenditures began to exceed tax income (from payroll taxes and from the taxation of Social Security benefits). In 2008, expenditures began to exceed total income (tax income plus all other sources of revenue), and Hospital Insurance (HI) assets (the balance of the HI trust fund at the beginning of the year) were used to meet the portion of expenditures that exceeded income. Expenditures have exceeded income every year from 2008 through 2015. In 2016 and 2017, the HI trust fund ran a small surplus, but in 2018 and 2019, the fund again experienced deficits. In 2020, the HI trust fund experienced a larger-than-normal deficit because of accelerated and advance payments made to providers during the COVID-19 pandemic (see the "Current Insolvency Projections" section). These payments were repaid in 2021-2023, resulting in HI trust fund surpluses in those years. In 2024, the surplus continued. In all future years beyond 2026, the trustees' projected expenditure growth is expected to continue to outpace growth in income, and the trust fund's accumulated assets will be drawn down to make up the difference between income and expenditures until the assets are depleted in 2033. At that time, the HI trust fund will no longer have sufficient funds to allow for the full payment of Part A expenditures. (See Table A-1, below, for historical and projected Medicare financial data through 2035.)

Appendix B. Historical Payroll Tax Rates

Appendix C. Changes in HI Trust Fund Insolvency Projections: 1997-2026

Although HI trust fund has faced insolvency since its inception, it has never become insolvent. The insolvency date has been postponed several times since the beginning of the Medicare program in 1965 through various methods. For example, in the early years of the program, the payroll tax rate was increased occasionally to maintain the financial adequacy of the HI trust fund. (See Appendix B for historical payroll tax rates.)

Other legislative changes have been made at various times to slow the growth in HI program spending, primarily by adjusting Part C plan and Part A provider payment methodologies. Generally, these measures have been part of larger budget reconciliation laws that attempted to restrain overall federal spending. (See Table C-1 below for a summary of changes each year in the solvency projections of the HI trust fund.)

This report was originally authored by former CRS Specialist in Health Care Financing Patricia A. Davis and was updated in 2021 by CRS Specialist in Health Care Financing Jim Hahn.

Footnotes

1.	For additional information on the Medicare program, see CRS Report R40425, Medicare Primer.
2.	Boards of Trustees, Federal Hospital Insurance and Federal Supplementary Medical Insurance Trust Funds, 2026 Annual Report of the Boards of Trustees of the Federal Hospital Insurance and Federal Supplementary Medical Insurance Trust Funds, June 9, 2026, Tables V.B1 and V.B3, at https://www.cms.gov/oact/tr/2026 (hereinafter, 2026 Report of the Medicare Trustees).
3.	Payments are made for beneficiaries enrolled in Part C from the Hospital Insurance (HI) and Supplementary Medical Insurance (SMI) trust funds based on estimates of HI and SMI spending under Part C.
4.	Medicare trustees reports from 1966 through 1994 are available on the Social Security History webpage at https://www.ssa.gov/history/reports/trust/trustyears.html. More recent reports are available on the CMS web page, "Trustees Report & Trust Funds," at https://www.cms.gov/data-research/statistics-trends-and-reports/trustees-report-trust-funds.
5.	For further information on Medicare financing, see CRS Report R43122, Medicare's Financial Status.
6.	Prior to 1991, the upper limit on taxable earnings was the same as for Social Security. The Omnibus Budget Reconciliation Act of 1990 (OBRA 90; P.L. 101-508) raised the limit in 1991 to $125,000. Under automatic indexing provisions, the maximum was increased to $130,200 in 1992 and $135,000 in 1993. The Omnibus Budget Reconciliation Act of 1993 (OBRA 93; P.L. 103-66) eliminated the upper limit entirely beginning in 1994.
7.	For additional detail, see archived CRS Report R41128, Health-Related Revenue Provisions in the Patient Protection and Affordable Care Act (ACA).
8.	Since 1994, the HI trust fund has had an additional funding source; OBRA 93 increased the maximum amount of Social Security benefits subject to income tax from 50% to 85% and provided that the additional revenues would be credited to the HI trust fund.
9.	There are about 200 federal trust funds. Congress creates trust funds that involve a commitment to use monies for a specific purpose, but it can alter the terms (e.g., receipts, outlays, or purpose) of the trust fund at any time. For additional information on how federal trust funds operate within the context of the federal budget, see CRS Report R41328, Federal Trust Funds and the Budget.
10.	Unlike marketable securities, special issues can be redeemed at any time at face value. Investment in special issues gives the trust funds the same flexibility as holding cash.
11.	For additional information, see the 2026 Report of the Medicare Trustees, Appendix F.
12.	2026 Report of the Medicare Trustees, p. 163.
13.	2026 Report of the Medicare Trustees.
14.	Under this program, health care providers were able to receive accelerated or advance payments for services provided or to be provided in the future. In 2020, about $67.1 billion was paid out of the HI trust fund for such payments. For additional information on this program, see archived CRS Report R46698, Medicare Accelerated and Advance Payments and COVID-19: Frequently Asked Questions.
15.	Memo from John D. Shatto and M. Kent Clemens, "Projected Medicare Expenditures Under an Illustrative Scenario with Alternative Payment Updates to Medicare Providers," June 18, 2025, at https://www.cms.gov/files/document/illustrative-alternative-scenario-2025.pdf.
16.	From time to time, it is reported that Medicare is on the verge of "bankruptcy"; however, in the context of federal trust funds, the term "bankruptcy" is not legally meaningful. It is true that a trust fund's expenditures can be greater than its income and that trust funds can have a zero balance, but, unlike private businesses, the federal government is not in danger of "going out of business" or having its assets seized by creditors. The federal government has unique fiscal challenges but also distinctive fiscal powers, such as the power to tax and to issue currency. Insolvency of the HI trust fund would not imply insolvency of the entire federal government or a cutoff of Medicare's other financing sources. As noted, Congress has often taken actions to increase the trust fund's revenues or reduce its expenditures when the Medicare HI trust fund has faced imminent insolvency.
17.	31 U.S.C. §1532. CRS Report R47600, Transfer and Reprogramming of Appropriations: An Overview.
18.	1998 Annual Report of the Board of Trustees of the Federal Hospital Insurance Trust Fund, p. 16, at https://www.cms.gov/Research-Statistics-Data-and-Systems/Statistics-Trends-and-Reports/ReportsTrustFunds/TrusteesReports.
19.	2026 Report of the Medicare Trustees, p. 28.
20.	Neither CMS nor the Medicare trustees have committed to specific plans for what would happen after insolvency.
21.	2026 Report of the Medicare Trustees, p. 26.
22.	2026 Report of the Medicare Trustees, p. 69.
23.	The specific factors contributing to the change in the 75-year actuarial balance projections from 2025 to 2026 are listed in Table III.B10 and described on page 74 of the 2026 Report of the Medicare Trustees.
24.	Congressional Budget Office, "The Long-Term Budget Outlook: 2026 to 2056," February 25, 2026, Tables 1a and 3, https://www.cbo.gov/publication/62044.
25.	2026 Report of the Medicare Trustees, Table II.D1.
26.	2026 Report of the Medicare Trustees, Supplementary Table III.B4.
27.	See Medicare Payment Advisory Commission, Figure 1-6, "The HI Trust Fund Covers a Declining Share of Total Medicare Spending," in Report to Congress: Medicare Payment Policy, March 2021, p. 17, at mar21_medpac_report_to_the_congress_secv2.pdf.
28.	2026 Report of the Medicare Trustees, Table II.F3. This amount is separate from and in addition to the payroll taxes used to fund the Part A (HI) portion of the program. For an overview of the federal tax system, see CRS Report R45145, Overview of the Federal Tax System in 2022.
29.	Congressional Budget Office, "Budget Options," December 2024, https://www.cbo.gov/budget-options, and Medicare Payment Advisory Commission, "Reports," Accessed May 6, 2026, https://www.medpac.gov/document-type/report/.