There are two possible reasons for not having health insurance in the United States. One is that you are not eligible for an existing health insurance program; the other is that you are eligible for a program, but not enrolled. Katherine Baicker, Amitabh Chandra, and Mark Shepard provide some evidence in “Achieving Universal Health Insurance Coverage in the United States: Addressing Market Failures or Providing a Social Floor?” (Journal of Economic Perspectives, Spring 2023, pp. 99-122).
The authors point out that there have been two main waves of expanding public health insurance programs. The first wave, in the 1960s, included Medicare for the elderly and Medicaid for families with low incomes. These programs reduced the share of the US population without health insurance from about 25% in 1963 to 12% by the mid 1970s, but the share floated up to about 15% by the early 2000s. The second main wave was the passage of the Patient Protection and Affordable Care Act in 2010, which included both a large expansion of Medicaid and income-based subsidies for private insurance to be purchased through “exchanges.” The rate of uninsured fell from about 15% to about 10%.
What about the rest? The authors write:
Figure 3 breaks down the uninsured into shares eligible for various sources of insurance as of 2021. On the one hand, this figure points to some gaps in social safety net programs. Not all states have expanded Medicaid under the Patient Protection and Affordable Care Act of 2010, leaving about two million very low-income Americans in twelve states to fall into a “coverage gap” (not eligible for Medicaid, but too low income to be eligible for nongroup market subsidies). Further, undocumented immigrants are not eligible for subsidies or Medicaid under the 2010 law, affecting perhaps 4 million people (or 13 percent of the uninsured). But together, these two groups account for less than one-fourth of the remaining uninsured. About 63 percent of the uninsured (about 18 million people)—by far the largest share—are low- or middle-income Americans who qualify for subsidized insurance (via Medicaid or a health insurance exchange) that they have not taken up. Indeed, under the more generous subsidies available since 2021, about 40–50 percent of the uninsured likely qualify for fully-subsidized coverage; that is, coverage with zero out-of-pocket premium for them (Rae et al. 2021). Thus, a substantial share of the uninsured could be covered by inducing take-up of benefits that would be free to them. These facts indicate that affordability is not the only, or even the main, barrier to universal coverage; other forces are at work as well.
The authors discuss the problem of “frictions” in reaching this group:
Addressing the frictions associated with enrolling in and retaining health insurance may substantially increase coverage by inducing those who already qualify for health insurance coverage at no out-of-pocket cost or with heavy subsidies to take it up. This group comprises about 22 million of the 29 million uninsured, including about 7.3 million people who already qualify for free Medicaid, 11.0 million people who qualify for health insurance through a state-level insurance “exchange” (with about half that group qualifying for free coverage), and 3.5 million people who could be receiving health insurance through an employer. For example, recent work has highlighted how seemingly small administrative burdens involved with insurance enrollment can strongly affect coverage outcomes (Domurat, Menashe, and Yin 2021; McIntyre, Shepard, Wagner 2021; Shepard and Wagner 2022; Wright et al. 2017). This is especially true when individuals transition between different forms of coverage—for instance, between Medicaid and exchange eligibility, or after losing a job with employer coverage and qualifying for Medicaid. Policies that target transitioning individuals for outreach or auto-enrollment could have a significant impact on take-up, though there are implementation challenges (Dorn, Capretta, and Chen 2018).
Finally, the existing safety net system of emergency departments, federally qualified health centers, public clinics, and charity care could be bolstered. Eligibility along with the bundle of free services expected to be delivered could be expanded. For example, providers of such services could be reimbursed with public funds for primary care and medicines that prevent acute events, not just for emergency department visits.
For many people–including some people who in fact have health insurance– access to health care isn’t just about insurance. Financial issues are of course part of the picture. But access to health care is also about being able to navigate the system in other ways, like knowing who to contact, where to go, how to get an appointment, and what can be provided at that location.