Maricopa County's uninsured rate of 10.6% tops the U.S. rate

Young adults in the Valley are more likely than any other age group to go without health insurance. About 16.8% of Maricopa County's young adults had no coverage, according to Census Bureau survey estimates covering 2020 through 2024.

That is well above the rate for middle-aged adults, at 12.4%, and for children and teens, at 8.4%. Seniors old enough for Medicare are nearly all covered. Just 1.1% of them lacked insurance.

The numbers arrive as open enrollment for 2027 health plans approaches. Enrollment in Arizona's Medicaid program has fallen (azcapitoltimes.com), and new rules are set to begin for some adults who rely on it (azahcccs.gov).

Young adults fall through the gaps

The uninsured rate for young adults is higher than the rate for middle-aged adults by 4.3 percentage points. That gap is statistically significant, which means it is very unlikely to be a quirk of the survey sample.

The pattern is not unique to the Valley. A national comparison for 2019 found this age group had a higher average uninsured rate than children, middle-aged adults or seniors (content.govdelivery.com).

Arizona shows a similar pattern. America's Health Rankings found the state's uninsured rate is higher among adults at the older end of the young-adult bracket than among all other age groups (AHR).

The survey does not say why young adults go without coverage. It counts who has insurance, not the reasons someone lacks it.

Across all ages, 10.6% of Maricopa County residents had no health insurance. Arizona's rate was 10.5%. The difference of 0.1 percentage points is within the margin of error, so the county and the state are effectively the same.

Both sit above the national rate of 8.4%. And the national figure has been climbing. SHADAC reported a significant rise in the U.S. uninsured rate from 2023 to 2024 in American Community Survey data (SHADAC).

More job-based coverage, less Medicaid

When Valley residents do have insurance, it is more likely to come through work. About 47.6% of Maricopa County residents had employer-based coverage and nothing else.

That compares with 43.0% statewide and 45.6% nationally. The county's share of people covered only through a job is higher than both.

Medicaid plays a smaller role here. Residents below Medicare age who relied only on Medicaid or a similar income-based program made up 13.6% of all county residents. The share was 14.9% for Arizona and 15.0% for the U.S.

Put together, the Valley leans more on private, job-based plans than the state or nation does. Yet its overall uninsured rate is in line with Arizona's and above the national figure.

These coverage groups do not add up to the whole population. People with Medicare, plans they buy on their own, or more than one type of coverage are counted in other categories.

Separate federal health data tells a similar story for working-age adults. CDC estimates put the share of Maricopa County adults without insurance at 12.9%, compared with 13.7% in neighboring Pinal County.

Maricopa's rate is lower by 0.8 percentage points, but that gap is within the margin of error. In practice, the neighboring counties look about the same.

The CDC figures use a different source and method than the Census survey. Readers should not compare them directly with the age-group rates above.

What comes next for coverage

Several changes could shift these numbers in the coming year. Enrollment in AHCCCS, Arizona's Medicaid program, has fallen, according to agency figures (azcapitoltimes.com).

Arizona also had fewer marketplace enrollments this year than in 2025, according to a report cited by the Tucson Sentinel (tucsonsentinel.com). Neither drop shows up in the Census estimates, which end with 2024.

More change is coming. Starting in January 2027, a new law requires certain Medicaid expansion adults to work, go to school, volunteer or meet a monthly earnings minimum to keep their AHCCCS coverage (azahcccs.gov).

That group typically includes low-income adults below Medicare age. AHCCCS says they will be particularly affected by the work rules and by regular eligibility re-checks (azahcccs.gov).

State officials expect the law to affect a large group of AHCCCS members, even though it does not change Medicaid's income limits (azcapitoltimes.com). The Arizona Medical Association says a change could also put Arizona refugees at risk of losing their health coverage (azmed.org).

Here is what to watch in the months ahead:

• Open enrollment for 2027 marketplace plans, and whether Arizona sign-ups keep falling.
• AHCCCS enrollment after the work rules take effect in January 2027.
• The next Census survey release, which will show whether young adults in the Valley are gaining or losing coverage.

For now, the data points to a clear pressure point. Young adults are the Valley residents least likely to have health insurance, even in a county where job-based coverage is more common than elsewhere.

How we did this

We used Census Bureau American Community Survey estimates pooled across 2020 through 2024 to compare uninsured rates by age and coverage type in Maricopa County, Arizona and the U.S. We tested whether the gap between young and middle-aged adults was larger than the survey's margin of error; the test score was 13.7 z-score, well above the usual threshold. We used the CDC PLACES 2025 release to compare working-age adults without insurance in Maricopa and Pinal counties.

Uninsured: a person with no health coverage of any kind at the time of the survey, including no Medicare, Medicaid, employer or self-purchased plan. Employer-based coverage only: insurance through a current or former employer or union, with no other type of coverage. Medicaid or means-tested coverage only: public coverage based on income, such as AHCCCS, with no other type of coverage. Here it counts residents below Medicare age and is shown as a share of all residents. AHCCCS: the Arizona Health Care Cost Containment System, Arizona's Medicaid program. Medicaid expansion adults: low-income adults below Medicare age who qualify for Medicaid under the expanded income limits. Margin of error: the range within which the true value likely falls. When a gap is within the margin of error, the figures being compared cannot be reliably told apart. Young adults, middle-aged adults, children and teens, seniors: the Census Bureau's age brackets used in this story. Seniors are the age group eligible for Medicare.

Limitations

• All figures are survey-based estimates with margins of error, not exact counts.
• The Census figures pool several years of responses, from 2020 through 2024, so they do not capture recent drops in Medicaid or marketplace enrollment.
• The data shows who lacks insurance, not why. It cannot tell us whether cost, job changes or other factors are behind the gaps.
• CDC PLACES figures come from a different source and method than the Census survey and should not be compared directly with Census age-group rates.
• The coverage categories shown do not add up to the full population. Medicare, self-purchased plans and combined coverage are counted separately.
• The effects of the new Medicaid work rules, which begin in January 2027, are not yet reflected in any of these numbers.

Sources

• U.S. Census Bureau, American Community Survey: Types of Health Insurance Coverage by Age (ACS 5-year 2020–2024), latest period 2024; retrieved Oct. 15, 2026. Data
• U.S. Census Bureau, American Community Survey: Public Health Insurance Status by Sex by Age (ACS 5-year 2020–2024), latest period 2024; retrieved Oct. 15, 2026. Data
• U.S. Census Bureau, American Community Survey: Private Health Insurance Status by Sex by Age (ACS 5-year 2020–2024), latest period 2024; retrieved Oct. 15, 2026. Data
• Centers for Disease Control and Prevention, PLACES: Local Data for Better Health: PLACES: Local Data for Better Health, County Data, 2025 release (PLACES 2025 release), latest period 2025; retrieved Oct. 15, 2026. Data