Enhanced subsidies for Obamacare have kept premiums affordable. Absent action from Congress, they will expire at the end of the year.

Here's how ACA marketplaces work, why enrollment has grown recently and what's at the heart of the US government shutdown.

Health insurance costs are set to rise next year as federal lawmakers fail to reach a deal to preserve health care subsidies.

“Health insurance in America is very expensive, because health care is very expensive,” said Katherine Baicker, a health economist who is the provost at the University of Chicago. “And that’s true in every market. What’s different is who is writing the check, and how easily perceived the full cost is to the individual who is being insured.”