Though the NBC Radio Network had long been affiliated with KFI in Los Angeles, that relationship did not extend into television when KFI-TV (channel 9, now KCAL-TV) signed on in August 1948.

[6] The call letters were changed again on November 11, 1962, when NBC moved the KNBC identity from its San Francisco radio station (which became KNBR) and applied it to channel 4 in Los Angeles.

[7][8][9] That call letter change coincided with the station's physical relocation from NBC Radio City to the network's color broadcast studio facility in suburban Burbank.

The station officially modified its callsign to KNBC-TV in August 1986,[10] shortly after NBC and RCA were purchased by General Electric; the -TV suffix was dropped effective September 6, 1995.

On January 1, 2014, Universal Sports transitioned into a cable- and satellite-exclusive service, causing its affiliates (such as KNBC) to replace the network and remove the channel from their digital signals entirely.

Channel 4 was the station of record for the NFL's Raiders during their tenure in Los Angeles from 1982 to 1994, and also aired any Lakers and Clippers games that were part of the NBA on NBC.

Furthermore, the station provided local coverage of Super Bowl LVI, which was held at SoFi Stadium in Inglewood and won by the Rams.

The first Super Bowl, which was also held at the Coliseum and broadcast on both NBC and CBS, did not air on KNBC or KNXT (channel 2, now KCBS-TV), due to the NFL's blackout policy of the time, which did not allow home telecasts of games regardless of whether they were sold out, including playoffs and the league championship game, and that policy extended to the host cities for the first six Super Bowls—Los Angeles, Miami (II, III, V), and New Orleans (IV and VI).

It will also be the home station when Los Angeles hosts the 2028 Summer Olympics and will share the Universal Studios lot with international broadcasters covering the Games.

Since 2024, the station aired select college football games involving the UCLA Bruins and USC Trojans as part of Big Ten Saturday Night.

NBC made similar changes to newscasts in other markets around the same time, and channel 4 shared the NewsCenter branding with sister stations WNBC-TV in New York City, WRC-TV in Washington, D.C., and WMAQ-TV in Chicago.

For most of the last 30 years, KNBC has waged a spirited battle with KABC-TV for the top-rated local newscast in Southern California, becoming a three-way race with KCBS-TV's ratings resurgence in 2006.

Throughout the late 1980s and into the early 2000s, KNBC's newscasts were the most-watched in the region, beating out every other station viewership-wise, which coincided with NBC's overall ratings at the time.

On December 6, 2011, KNBC entered into a partnership with public radio station KPCC as part of a larger effort by NBCUniversal to partner with non-profit news organizations following its acquisition by Comcast.

Former anchor Paul Moyer worked two stints at channel 4; first from 1972 to 1979 (when he began a 13-year run at rival KABC-TV) and from July 1992 until his April 2009 retirement.

It led Horowitz to start a successful campaign to ban "look-alike" toy guns in several states, including California and New York.

Other notables who have worked at KNBC early in their careers prior to joining the network include Bryant Gumbel, Ross Porter, Pat Sajak, Kent Shocknek, Bob Abernethy, Keith Morrison and Tom Snyder.