"We want as many customers as possible to remain enrolled in marketplace coverage, so we are giving these individuals a last chance to submit their documents before their coverage through the marketplace will end," said Marilyn Tavenner, administration for the Centers for Medicare and Medicaid Services, at the time of the warning on Aug. 18. Tavenner's agency operates HealthCare.gov.
Friday's deadline is just for those enrollees of plans sold through the marketplace, which serves residents of the 36 states that did not operate their own health insurance exchanges this year.
As of May, CMS has said, there were about 970,000 HealthCare.gov customers with citizenship or immigration data matching errors. That number represents about 18 percent of the total number of enrollees on HealthCare.gov.
Since then, CMS has closed about 450,000 cases after hearing from enrollees, and was in the process of resolving another 210,000 more.
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On the heels of the warning, an Aug. 28 story in USA Today reported that immigration advocates and insurance agents have said that even people who provided adequate documentation when they enrolled were being told there were questions about their eligibility. That story also quoted agents who described how some customers were unable to access their HealthCare.gov accounts to provide requested documents, and how even people who were able to upload such paperwork were told by CMS that it wasn't received.
CMS spokesman Aaron Albright on Friday said, "If people submit their information, they can call our call center and see if we have received the information. That list is updated daily." The call center number for HealthCare.gov is 800-318-2596.
An unknown number of other people who bought insurance through one of the 15 exchanges operated by individual states of the District of Columbia also have pending questions about their eligibility because of their citizenship or immigration status.
Kentucky's exchange mailed "little more than 1,700 individuals who did not submit the required information regarding citizenship, income or incarceration status," according to the spokeswoman for that marketplace, known as kynect. She added, "kynect has seen an overwhelmingly positive compliance rate as a result of these notices."
Kentucky has set a deadline of next Wednesday for the requested documentation to be submitted.