May 21 (Bloomberg) — About half of uninsured Americans surveyed didn't try to sign up for health coverage under Obamacare because they said they couldn't afford it, with most unaware that financial assistance was available.

Cost also was the main reason given by 39 percent of people who looked for insurance and decided against it, according to a survey of 1,524 people by Enroll America, a nonprofit group allied with the White House that organized enrollment efforts in 11 states. Only 26 percent of those who didn't enroll were aware that there were government subsidies available, compared with 56 percent of people who did sign up.

About 8 million Americans signed up for private plans using the marketplaces created by the Patient Protection and Affordable Care Act in 2014, beating projections, and at least 13 million are expected next year. Today's survey shows that education and outreach efforts will be "critically important" to get people to enroll next year, said Anne Filipic, Enroll America's president.