Behind the national numbers are three key trends, said David Johnson, chief of the U.S. Census Bureau's division of Housing and Household Economic Statistics.
• For the first time in a decade, there was no decline in the ranks of privately insured.
• Young adults, ages 19 to 26, saw the biggest jump in coverage, up 2.2 percent. Forty percent of them were able to stay on their parents' health plans, an early provision of federal health reform, Johnson said.
• More retirees qualified for Medicare and more low-income citizens enrolled in Medicaid.
Johnson cautioned against resting too much on Utah's numbers, saying more accurate state-level data will be released next week.
But the census figures mirror Utah Department of Health estimates showing years of home-grown health reforms have failed to put a dent in the uninsured.
"These numbers affirm the need to fully implement federal health reform," said Shelly Braun, reform initiatives director at the Utah Health Policy project.
In Utah, young adults have long been able to stay on their parents' policies, but the law didn't apply to married couples or large employer plans.
Utah was the second state to create a health insurance exchange. But it's been slow to catch on; about 32 percent of the 1,866 small business workers who have purchased insurance through the portal were previously uninsured.
"Insurance, whether private or public, is the door we walk through to get medical care," said Braun.
Utah's Republican leaders are waiting until after the November election to decide which parts of the Affordable Care Act to embrace, including a proposed expansion of the low-income health program Medicaid. They've criticized the expansion as a budget-breaker, noting the health law does nothing to control costs.
Big states with more permissive Medicaid programs may have skewed national results, said Sen. Wayne Niederhauser, R-Sandy. "We have a lean program and a lot of people who are eligible, but don't enroll because of our cultural of self reliance."
Government programs remain a growing source for coverage. For the fifth consecutive year, enrollment in public programs such as Medicare, Medicaid and insurance for the military, grew, according to census data.
Health insurance highlights, 2011
Children are uninsured at roughly the same rate as in 2010.
There was also no real change for Hispanics, while the uninsured rate among blacks and whites dropped slightly.
There was a break from erosion in employer-based coverage; the workplace remains the path to coverage for 55 percent of the population.
The percentage of people covered by Medicaid rose nearly a percentage point, as did enrollment in Medicare.
Source: U.S. Census Bureau, 2012 Current Population Survey