Raleigh, N.C. — York Simpson Underwood, one of the Triangle’s top real estate firms led by former Raleigh Mayor Smedes York, has been acquired by the real estate arm of billionaire Warren Buffet’s empire.

As part of the deal, York Simpson Underwood will be merged with Prudential Carolinas Realty, which is already owned by Buffett’s HomeServices America.

The combined venture will be called Prudential York Simpson Underwood Realty and will be based in Raleigh.

York Properties, the commercial property venture operated by Smedes York, is not part of the merger, according to a spokesperson for HomeServices America.

The acquisition creates the largest real estate entity in terms of listings in the region. According to the companies, York Simpson Underwood is No. 1 among realtors in average home sales price with prudential Carolinas Realty second.

York, a legend in Triangle real estate, will serve as chairman of the combined venture.

HomeServices America, which is based in Minnesota, is part of Buffett’s Berkshire Hathaway Company.

Financial terms were not disclosed.

York Simpson Underwood maintains six offices across the Triangle and in the Pinehurst area. Its 250 agents produced closings worth more than $700 million in 2007.

According to the companies, the merger will double the market share and number of agents for HomeServices in the Triangle.

“This merger creates the premier Triangle real estate company,” York said in a statement. “We are combining two strong firms within the Triangle into an even stronger organization. By joining forces with HomeServices, we will be unmatched in our ability to serve the real estate and corporate relocation needs of new and existing clients in the Triangle. Our commitment is to make this merger seamless for our customers, who will continue to be served by their existing agents.”