The film premiered in New York City on November 27, 1976, and went into wide release shortly afterward.
The film became one of the big hits of 1976–77 and got big receipts and reviews. Vincent Canby, in his November 1976 review of the film for The New York Times, called the film "outrageous ... brilliantly, cruelly funny, a topical American comedy that confirms Paddy Chayefsky's position as a major new American satirist" and a film whose "wickedly distorted views of the way television looks, sounds, and, indeed, is, are the satirist's cardiogram of the hidden heart, not just of television but also of the society that supports it and is, in turn, supported."
On review aggregator website Rotten Tomatoes, Network currently holds a 91% "fresh" rating based on 53 reviews.
In a review of the film written after it received its Academy Awards, Roger Ebert called it a "supremely well-acted, intelligent film that tries for too much, that attacks not only television but also most of the other ills of the 1970s," though "what it does accomplish is done so well, is seen so sharply, is presented so unforgivingly, that Network will outlive a lot of tidier movies." Seen a quarter-century later, Ebert added the film to his The Great Movies list and said the film was "like prophecy. When Chayefsky created Howard Beale, could he have imagined Jerry Springer, Howard Stern, and the World Wrestling Federation?"; he credits Lumet and Chayefsky for knowing "just when to pull out all the stops." The film also ranks at number 100 in Empire magazine's list of the 500 Greatest Films of All Time.
Not all reviews were positive: Pauline Kael in The New Yorker, in a review subtitled "Hot Air", criticized the film's abundance of long, preachy speeches; Chayefsky's self-righteous contempt for not only television itself but also television viewers; and the fact that almost everyone in the movie, particularly Robert Duvall, has a screaming rant: "The cast of this messianic farce takes turns yelling at us soulless masses." Michael Billington wrote, "Too much of this film has the hectoring stridency of tabloid headlines", while Chris Petit in Time Out described it as "slick, 'adult', self-congratulatory, and almost entirely hollow", adding that "most of the interest comes in watching such a lavishly mounted vehicle leaving the rails so spectacularly."