TVB ePort has secured the support of 605 committed stations in 178 markets, representing 96.1 percent of the United States, the Television Bureau of Advertising announced today. It will be available in 98 of the top 100 markets.

“TVB ePort’s momentum is continuing to swell—we passed the 500-station mark just under a month ago,” said TVB President Chris Rohrs. “We are still hearing from additional TV stations every day, and we expect ePort will be everywhere.”

The project was announced on Feb. 21 with an infusion of seed money from the National Association of Broadcasters, with the remainder of funding to come from broadcast groups and rep firms.

TVB ePort is now in beta test mode, with selected spot TV buyers sending orders to selected stations electronically. The entire suite of open standard transactions—from avail through invoice for stations’ airtime, Web sites, digital subchannels and other multiplatform offerings—is expected to be available through TVB ePort by the second quarter of 2008.

The 605 stations are drawn from 63 broadcast groups: ABC Owned Television Stations, Acme Television, Allbritton Communications Co., Banks Broadcasting, Barringer Broadcasting, Belo Corporation, Block Broadcasting, Bonneville International, California-Oregon Broadcasting, CBS Television Stations, Citadel Communications, Cordillera Communications, Cowles Publishing, Cox Television, CP Media, the Dispatch Broadcast Group, Drewry Communications, Duhamel Broadcasting Enterprises, E.W. Scripps Company, Emmis Communications, Fisher Communications, Fox Television Stations, Freedom Broadcasting, Gannett Broadcasting, Global Broadcasting, Hearst-Argyle Television, Hoak Media, Hubbard Broadcasting, JKB Associates, Journal Broadcast Group, KAZT LLC, Larry H. Miller Communications, LIN Television Corp., Max Media, Max Media of Montana, McGraw-Hill Broadcasting, Media General Broadcast Group, Meredith Broadcasting, Montgomery Communications, Morgan Murphy Stations, National Communications, NBC Universal Television Stations, New Vision Group, News-Press & Gazette, Nexstar Broadcasting Group, Ottumwa Media Holdings, Pappas Telecasting Companies, Post-Newsweek Stations, Quincy Newspapers, Ramar Communications, Raycom Media, Sagamore Hill Broadcasting, Sarkes Tarzian Inc., Schurz Communications, Second Generation Television, Sinclair Broadcast Group, Smith Media, South Jersey Radio, Telemundo Group, Tribune Broadcasting, the University of Missouri, Woods Communication Corp and Young Broadcasting.