S-F Radio: Cumulus Goes Silent On 560 AM

Cumulus Media has suspended operations at 560 AM in San Francisco, a station now known as KZAC, which had previously operated as KSFO for many years. This closure marks the end of a century-long presence on the airwaves for the station, which first began broadcasting in 1925. The move is part of a broader strategic effort by Cumulus to optimize its portfolio and reallocate resources across its local markets.

On March 3, KZAC (560 AM) went silent, as part of a significant realignment in Cumulus Media’s San Francisco cluster. Earlier, on January 1, 2025, the company shifted KSFO’s conservative talk format from its long-time home at 560 AM to a more powerful 50,000-watt signal at 810 AM, previously occupied by KGO. The 560 AM frequency was then reassigned the call letters KZAC, initially retaining a simulcast of KSFO’s programming. However, Cumulus later decided to take KZAC off the air entirely, informing the FCC that it is "in the process of deciding whether to change the format or sell the station."

The closure reflects Cumulus Media’s ongoing efforts to streamline operations amid challenging market conditions. The company has stated that certain stations, including KZAC, are no longer a strategic fit within their respective markets. 

The decision aligns with broader cost-cutting measures; during a recent earnings call, CEO Mary Berner noted that Cumulus had reduced expenses by $35 million in Q4 2024 alone, with a cumulative $128 million cut between 2019 and Q3 2024, aiming for a 27% overall expense reduction by the end of 2025. The suspension of KZAC’s operations is described as impacting "very few individuals," suggesting a minimal staffing footprint at the station by the time it went dark.

560 AM Coverage (5 Kw)

Historically, 560 AM had a rich legacy in the Bay Area. Originally licensed as KTAB in Oakland in 1925, it moved to San Francisco and became KSFO in 1935. Over the decades, it evolved from religious and commercial formats to a full-service station under Golden West Broadcasters in the 1950s and 60s, and later became a prominent conservative talk outlet in the 1990s under Capital Cities/ABC and then Cumulus Media, which acquired it in 2011. The station was known for hosting notable figures like Michael Savage and local sports broadcasts, cementing its place in Northern California’s radio history.