Yahoo said today that all of its real estate listings will now be powered by Zillow.
Zillow will also sell local advertising on both sites, and the 4 million listings on Zillow will appear on Yahoo Real Estate.
Real estate agents will be able to advertise locally on Yahoo Real Estate, and home buyers will have more access to listings on the site along with more photos.
"This partnership brings together the scale of Yahoo's audience with the depth of Zillow's real estate listings," Greg Hintz, head of Yahoo Listings, said.
"No other real estate websites are better suited to bring such a vast offering to agents, brokers and advertisers.
The Yahoo and Zillow relationship began in 2006 when Yahoo Real Estate incorporated Zillow's Zestimate home valuations.