The Affordable Care Act introduced health insurance Marketplaces in 2014 to help provide access to affordable insurance coverage. Using early release data from the National Health Interview Survey, we examined the characteristics of adult Marketplace enrollees in 2015, how they have changed since 2014, and how they differ between Medicaid expansion and nonexpansion states. We found that coverage through the Marketplaces increased in 2015, with more nonelderly adult enrollees insured all year and fewer reporting health care affordability problems than in 2014. In 2015 more Marketplace enrollees in Medicaid nonexpansion states reported trouble paying family medical bills, compared to those in expansion states.