Nearly a third of people overall — including a third of people without health insurance — said they had not heard anything about the sign-up period for individuals who buy health plans on their own, according to the survey by the Kaiser Family Foundation.
Open enrollment started Nov. 1 and runs through Dec. 15 in most states, including Pennsylvania and New Jersey. Advocates fear enrollment will decline this year because President Trump has been repeatedly saying the health law is "dead," and his administration severely cut funding for publicity and in-person assistance.
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One factor that could be pushing more people to sign up earlier this year is the open-enrollment season was cut in half from three months to 45 days for the states relying on the federal exchange.
Several state health-insurance exchanges have also said early sign-ups are running higher than last year. The Colorado insurance exchange on Thursday said it has enrolled more than 22,000 people in the first two weeks — a 33 percent jump from last year's first weeks.
In the previous open-enrollment season, 12.2 million people nationwide selected individual market plans through the marketplaces. The number dropped off during the year because not everyone paid and some found coverage elsewhere.
Forty-five percent of all respondents to the Kaiser Family Foundation survey and 52 percent who said they were uninsured said they have heard less about open enrollment this year compared to previous years.
Insurers are trying to pick up some of the challenges of publicizing enrollment, and some of those ads are getting noticed.
The percentage of survey respondents who said they saw ads attempting to sell health insurance increased from 34 percent to 41 percent between the October and November KFF tracking polls. The share who say they saw ads that provided information about how to get health insurance under the ACA increased from 20 percent to 32 percent.
The poll found that nearly eight in 10 Americans were aware the Affordable Care Act was still in effect.
The survey of 1,201 adults, which was conducted Nov. 8-13, has a margin of error +/-3 percent.