Two of the nation’s biggest real estate websites could soon become one.

Zillow Inc. is in talks to buy rival Trulia, Bloomberg reported Thursday, citing people familiar with the negotiations. Though the merger may not come to fruition, the sources also said a deal valuing Trulia at $2 billion could be announced as soon as next week.

The two sites are by far the largest in the burgeoning online real estate industry, combining for 84.6 million unique visitors in May, according to a report by Clareity Consulting. That's three times as many as their next closest competitor, National Assn. of Realtors-affiliated Move Inc.

The sites, with their troves of easily mapable and searchable listings, have transformed the way many consumers shop for a house. But they have also at times faced grumbling from real estate agents and market-watchers for inaccurate and incomplete data.

If Zillow and Trulia do join forces, the online real estate business would follow the path of other e-commerce industries toward consolidation around a couple of huge players, even as smaller outfits such as Seattle-based Redfin try to gain traction.

Share prices for both companies jumped on the news Thursday morning.