Shares of the Seattle-based company nosedived 24% to $30.96.
Revenue totaled $343 million, up from $281.84 million a year ago, but missed Wall Street's expectations of $343.7 million. Zillow posted quarterly earnings on an adjusted basis of 18 cents a share, 1 cent better than analysts' estimates.
Looking ahead, Zillow said it expected fourth-quarter revenue to range from $340 million and $357 million, below Wall Street's expectations of $368 million.
Zillow also lowered its full-year revenue guidance to a range of $1.31 billion to $1.32 billion, from a previously adjusted range of $1.32 billion to $1.35 billion.
Canaccord Genuity Group Inc., meanwhile, cut Zillow's stock price target cut to $50 from $60.
Zillow's brands include Trulia, StreetEasy, HotPads, Naked Apartments and RealEstate.com.