Last year, for the first time, most Americans were required by the Affordable Care Act to have some kind of health coverage or be subject to a tax penalty. But this year is the first that the tax is being collected—and the first time that income tax returns ask about filer's health coverage.
The Kaiser poll found that 53 percent overall—and 57 percent of people without health insurance—know that this is the first year they are required to disclose their coverage status.
About a third overall named a different year for the requirement, and 16 percent admitted to not knowing when the requirement starts.
Among respondents who personally completed and filed their returns, 76 percent said they had seen "a place to indicate whether they had health insurance," according to Kaiser.
But the remaining self-filers either didn't see such a place, or were unsure if they did see it, the poll found.
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Continued ignorance about the key ACA feature recently led the federal government and most states to announce a special enrollment period in Obamacare insurance plans for tax season, after the original Feb. 15 sign-up deadline had passed.
The grace period, which began in most of the U.S. this week, allows uninsured people who didn't know they would be subject to the Obamacare penalty until tax season to sign up for a 2015 health plan.
A top federal official last week said that the grace period will not be offered again.
But Kaiser Family Foundation CEO and President Drew Altman noted that "a solid majority" of respondents to the poll were in favor of offering that kind of waiver next year.
Fifty-eight percent of respondents said uninsured people should be able to enroll in coverage in order to avoid paying the Obamacare fine.
"It just seems reasonable to them," Altman said.