Despite spending more than $1 trillion on health insurance each year, many U.S. consumers are making poorly informed decisions – and paying for their lack of understanding.

According to the latest Health Insurance Literacy Survey from HealthCare.com:

• 1 in 4 Americans say lack of health insurance understanding caused them to receive a higher-than-expected medical bill.
• Half believe that copays count toward deductibles, when they generally do not.
• Half of respondents say they can't afford health insurance without employer coverage.
• 3 in 10 stay in jobs they don't like or take jobs they don't want so they can receive health insurance.

The survey of 1,000 consumers younger than 65 identified several broad areas of concern.

Confusion and complexity. The complexity of U.S. health insurance creates numerous hurdles for Americans in getting the most out of their health care dollar. Since 2003, for example, federal health savings accounts offer savings by providing the opportunity to pay medical expenses with pretax dollars. Two decades later, however, fewer than half of respondents are able to correctly identify HSAs, and 1 in 5 are unable to identify a single feature of HSAs out of four listed options.