Spinebreaker is a San Jose death metal and hardcore band formed in 2014, blending the savagery of death metal with hardcore's directness and aggression in the Bay Area's active heavy underground.

Los Angeles industrial metal outfit Spineshank were a key part of the late-1990s/early-2000s Roadrunner Records roster, blending Fear Factory's mechanized precision with nu-metal's groove and electronic textures. Albums like 'The Height of Callousness' and 'Self-Destructive Pattern' showcased a band more technically accomplished and sonically adventurous than many of their nu-metal peers, incorporating drum machines, samples, and atmospheric programming alongside crushing guitar riffs. After disbanding in 2004 and briefly reuniting, Spineshank left behind a catalog that rewards revisiting for fans of the industrial-metal crossover era.

Spira is a raw black metal project from Santa Rosa, California, formed in 2023, embracing the primitive, lo-fi aesthetic of second-wave black metal with a harsh and deliberately unpolished sonic approach.

Spiritual Demise is a Los Angeles black metal band formed in 2009, delivering cold, misanthropic black metal that contrasts sharply with the city's sunlit surroundings through aggressive songwriting and raw production.

Spiritual Eclipse is a black/death metal band from Modesto, California, formed in 2002, blending the tremolo-picked aggression of black metal with the brutal, down-tuned heaviness of death metal.

Spirotin is a Los Angeles band formed in 2021 that merges black metal and metalcore, combining the atmospheric malice and tremolo aggression of black metal with the rhythmic heaviness and breakdowns of metalcore.

Bay Area brutalists Spite deal in relentlessly aggressive deathcore built on guttural vocals, punishing breakdowns, and a suffocating atmosphere of nihilistic rage. Vocalist Darius Tehrani's intense delivery and the band's uncompromising sonic violence on albums like 'Nothing Is Beautiful' and 'Dedication to Flesh' have made them a leading force in modern deathcore's heaviest wing. Spite's live shows are notorious for their intensity, regularly turning venues into war zones of swirling pits and crowd surges.

Spitkiss is an industrial and groove metal band from San Jose, California, formed in 1994, combining the mechanical textures and electronic elements of industrial metal with the mid-tempo, riff-locked heaviness of groove metal.

Splatter Analyst is a California slam and brutal death metal band formed in 2024, built on crushing breakdowns, guttural vocals, and the low-tuned brutality that defines the modern slam aesthetic.