Do hospitals charge uninsured patients the highest prices?

Yes, hospitals usually charge uninsured patients the highest prices. The Wall Street Journal reports:

Cash payers are often charged more than insurance companies for the same service by the same hospital, according to a WSJ analysis of previously confidential data

To people who follow the healthcare industry, this is no surprise.  Hospitals and other healthcare practices use wishlist pricing.  That means they set arbitrarily high prices before negotiating with insurance companies.  After negotiating, which insurance companies demand, the actual prices are much lower.  However, uninsured people don't have an insurance company to negotiate on their behalf.  And healthcare practices generally don't bother to create separate prices for the uninsured.  They simply use the wishlist they cooked up, even though those prices were deliberately much too high.

Even the government acknowledges: "People without insurance pay, on average, twice as much for care."

Check out Hacker News for more interesting commentary on this story.