SEATTLE and SAN FRANCISCO – Zillow, Inc. (NASDAQ: Z) has entered into a definitive agreement on Monday to acquire Trulia, Inc. (NYSE: TRLA) for $3.5 billion in a stock-for-stock transaction.

The transaction is expected to close in 2015.

The combined company will maintain both the Zillow and Trulia consumer brands, offering buyers, sellers, homeowners and renters access to vital information about homes and real estate for free, and providing advertising and software solutions that help real estate professionals grow their business.

Trulia CEO Pete Flint will remain as CEO of Trulia reporting to Zillow CEO, Spencer Rascoff, and will join the Board of Directors of the combined company.

Both Zillow and Trulia are primarily media companies, generating the majority of revenue through advertising sales to real estate professionals. Despite continued growth as public companies, significant opportunities of scale remain as the majority of advertising dollars in the real estate sector have yet to migrate online or to mobile.

Zillow and Trulia are two rapidly growing real estate sites on mobile and the Web, enabling advertisers to reach a large and expanding consumer base.

In June, Zillow reported a record 83 million unique users across mobile and web. For the same month, Trulia reported a record 54 million monthly unique users across its sites and mobile apps.

Goldman, Sachs & Co. acted as the exclusive financial advisor, and Shearman & Sterling LLP and Perkins Coie LLP acted as legal counsel to Zillow. J.P. Morgan Securities LLC acted as a financial advisor, and Goodwin Procter LLP and Wilson Sonsini Goodrich & Rosati acted as legal counsel to Trulia. Qatalyst Partners LP also acted as a financial advisor to Trulia.

The companies will host separate conference calls to discuss each company’s second quarter results. Trulia is set for July 31 at 5 p.m. EDT and Zillow on Aug. 5 at 5 p.m.