The U.S. real estate website operator Zillow is looking to acquire its rival Trulia, Bloomberg reported on Thursday, citing people familiar with the matter. The move would combine the two real estate websites with the most traffic in the United States.
Shares of both companies were up following the report. Trading on the two firms was briefly halted earlier.
Trulia's shares rose by nearly 40 percent to an all-time high, while Zilliow's shares jumped 25 percent to a record high of $157.61.
Zillow, which has a market value of about $5 billion, could value Trulia at as much as $2 billion in a purchase, and a deal could be announced as soon as next week, reported Bloomberg.
Zillow and Trulia, the two most visited real estate websites in the United States, list properties for sale or rent on behalf of homeowners and agents. They gets most of their revenue from subscriptions from real estate agents.
The websites had more than 85 million unique visitors in June and accounted for 89 percent of all traffic to real estate sites, according to ComScore, Bloomberg said.
Zillow spokeswoman Dawn Lyon said the company wouldn't comment on rumors, and Trulia did not immediately respond to CNBC's requests for comment.
Last year, Trulia acquired a marketing firm and in February had announced it would expand spending in that area. Stock had dropped 19 percent following the news.
—By CNBC.com. Reuters contributed to this report.