YellowPages.com, owned by AT&T, said it is opening a Seattle office.

The opening corresponds with analyst expectations that online advertising in directories will increase as more people turn to the Internet rather than a phone book for numbers and addresses. In fact, online directory ads are expected to increase by 31 percent in the next four years, according to the Kelsey Group, an analyst firm.

The company expects the Seattle office to open on April 23, with as many as 30 employees who will be signing up local advertisers.

Seattle and Denver are among the company's first offices to be opened west of the Mississippi, following new offices in Philadelphia, New York City, Boston and others.

YellowPages.com said Seattle was selected because a large percentage of people who use its site are from there.

YellowPages.com had more than 1 billion network searches last year.