No. 1 Reason for Letterman Remaining in New York . . . : Television: CBS buys the Ed Sullivan Theater so the comedian’s late-night show won’t have to move to L.A.

CBS confirmed Monday that it is buying the historic Ed Sullivan Theater here as the new home for David Letterman’s late-night comedy show so he won’t have to move to Los Angeles after leaving NBC.

CBS will pay an estimated $4 million to purchase the Broadway theater-district facility, which housed the network’s popular “Ed Sullivan Show” for many years.

The network plans to make renovations in the theater and adjacent office buildings to house a number of television production offices. When finished, the theater will hold an audience of about 400 people.

“We never seriously considered leaving New York,” CBS Broadcast Group President Howard Stringer said in an interview. “David wanted to stay here from the word go. We looked at the new state-of-the-art (CBS) facilities in Los Angeles, but that only slowed down the process when we saw what was possible technically. Los Angeles offers many advantages. But David and the staff feel comfortable doing the show here, and the show has been a success here. When you’re beginning a new show, it makes sense to try to continue a winning streak.”

CBS said, however, that the show will travel to Los Angeles at least once a year for an “extended visit.”

Letterman’s producers had considered the easier availability of guests in Los Angeles in their decision-making, but they noted that there already are many talk shows competing for guests there. The staff also wanted to stay in New York, and there was some concern about the practicality of moving everyone between the time the NBC show ends June 25 and the new one begins on CBS in late summer.

Before the decision was made to purchase the Ed Sullivan Theater, the Letterman producers had considered the CBS Broadcast Center in New York, a facility on the west side of Manhattan that houses both CBS News and CBS soap operas.

The Broadcast Center would have offered Letterman some of the humor-making opportunities he has enjoyed at NBC’s Rockefeller Center studios--roaming the halls with cameras, harassing the “Today” show and occasionally running into other NBC personalities--but the studios there were considered too cramped to house the Letterman show and studio audience without disrupting other CBS programming.