26% of ACA enrollees were uninsured; 87% paying premiums, McKinsey finds

Roughly a quarter of individuals who purchased health plans on and off state and federal exchanges were previously uninsured, according to the latest survey results from the McKinsey Center for U.S. Health System Reform.

That figure is essentially unchanged from the research firm's last nationwide poll conducted in February of individuals who are eligible to purchase plans through the exchanges.

The McKinsey survey also found that 87% of respondents who had enrolled in coverage indicated that they had made their first premium payments. That was up from 77% in the February poll and aligns with figures that some large insurance companies have released.

However, younger enrollees were less likely to follow through with premium payments, with 78% of 18- to 29-year-old respondents reporting that they had paid their first bill.

Of those individuals surveyed who previously had coverage, 90% report enrolling in a plan for 2014. By contrast, only 13% of survey respondents who were previously uninsured reported signing up for coverage.

Cost remained the biggest factor in keeping individuals from enrolling in a plan. Roughly 60% of respondents who shopped for coverage but didn't enroll in a plan cited affordability as the reason for not completing the transaction. Of those respondents, 88% were eligible for subsidies. Individuals with incomes up to 400% of the federal poverty threshold can access subsidies under the Patient Protection and Affordable Care Act.

But the McKinsey survey found that ignorance about the availability of subsidies remained high for uninsured individuals. Two-thirds of those individuals who cited affordability as the primary reason why they did not enroll in a plan were unaware of the availability of premium subsidies. That was consistent with findings from the February survey.

McKinsey has conducted five online surveys of individuals eligible to buy coverage through the exchanges since the open enrollment period began Oct. 1. A total of 9,533 individuals were surveyed. The most recent polling took place between April 7 and 16 and included 2,874 respondents.

Follow Paul Demko on Twitter: @MHpdemko