America's 10 most expensive ZIP codes revealed

A new analysis of the 10 most expensive ZIP codes in the U.S. finds that California continues to be home to a significant portion of the nation's most luxurious properties.

Economists at Realtor.com sought to find the 10 most expensive communities in the U.S. by focusing on areas with at least 30 active listings in January to identify qualified ZIP codes. From there, they ranked markets by median listing price. And, in cases when that was tied in two markets, the median square footage of the listed properties was used as a tiebreaker.