|City of license||Denver, Colorado|
|Broadcast area||Denver, Colorado|
|Slogan||Real. Music. Variety.
Continuous Christmas Music (November- December)
|Frequency||101.1 MHz (also on HD Radio)|
|First air date||1968|
Christmas music (November-December)
HD2: OFF AIR
|Callsign meaning||Sounds like "cozy"|
|Owner||Bonneville International Corporation|
|Sister stations||KYGO-FM, KKFN, KEPN|
KOSI is a commercial radio station located in Denver, Colorado, broadcasting on 101.1 FM. KOSI airs an adult contemporary music format branded as "KOSI 101.1". Its studios are located in Greenwood Village|Colorado, and the transmitter is on Lookout Mountain near Golden.
KOSI-FM signed on in 1968 airing an easy listening/beautiful music format. At the time, it was paired with KOSI 1430 AM. The stations were owned by Bill Armstrong, who would later become a Republican congressman and two term U.S. Senator. Armstrong sold KOSI-FM to Westinghouse Broadcasting in 1981. KOSI-AM then became KEZW in March of that year. In 1988, Westinghouse sold KOSI and KEZW to D&D Broadcasting, Inc. for $15.5 million.  By 1990, the format evolved into its current mainstream adult contemporary music format. Tribune Broadcasting owned the station from January of 1993 to December of 2002, when it was sold to Entercom. From 2007 to 2011, KOSI aired the syndicated Delilah radio show. Delilah has since been replaced with local programming.
On July 14, 2015, as part of their merger with Lincoln Financial Media, the Department of Justice forced Entercom to spin off KOSI, KYGO-FM, KKFN and KEPN to Bonneville International in exchange for Bonneville's KSWD in Los Angeles to meet ownership limits (this would also result in KOSI and KEZW being separately owned for the first time). Both Bonneville and Entercom began operating their new clusters via Time Brokerage Agreements on July 17, 2015 until the transaction was consummated on November 24, 2015.
KOSI is the only radio station in the Denver area to switch its format entirely to Christmas music during the Christmas season. The change generally takes place during the week of Thanksgiving and continues until 12:00 AM on December 26, at which point the format goes back to soft adult contemporary. In 2008 the Christmas music continued until December 27.
- Official Website
- Query the FCC's FM station database for KOSI
- Radio-Locator information on KOSI
- Query Nielsen Audio's FM station database for KOSI