NBC and the Warner Brothers television studio concluded the biggest deal ever for a half-hour television program last night, a one-year renewal for the comedy ''Friends'' that will exceed the per half-hour price the network paid for ''E.R.'' in 1998.

The deal will bring back the entire six-person cast for what is being called the last season of the series, and it will pay each one a salary of $1 million an episode -- a total of $22 million a season if the show produces the expected 22 episodes.

The deal underscored the critical position ''Friends'' holds on NBC's prime-time schedule. This season the show has rebounded from what seemed to be a steady decline over the last several seasons to score its biggest ratings in five years -- and the biggest in all of television. A relieved Jeff Zucker, the president of NBC Entertainment said, ''This is a great day.''

For the networks, the increasing prices being paid to long-running comedy hits like ''Friends'' and ''Frasier'' are a further indication of how dependent the networks have become on keeping their aging hits on the air, especially in comedy. No recent comedy series has been able to approach the success of ''Frasier,'' ''Friends'' and ''Everybody Loves Raymond,'' all of which began in the mid-1990's.