Spellbinder is a power metal band from Oakland, California, formed in 2001, delivering soaring, melodically driven power metal with the high-register vocals and twin-guitar harmonies characteristic of the American power metal style.

Spellcast is a symphonic black metal band from Lakewood, California, formed in 2012, layering orchestral arrangements and grandiose keyboard textures over black metal's raw aggression in the tradition of European symphonic black metal.

Spellgrinder is a heavy metal band from Twentynine Palms, California, formed in 2023, playing traditional heavy metal from the high desert of the Mojave with a sound rooted in classic metal song craft.

Spinal Tap is the Los Angeles fictional heavy metal band created for Rob Reiner's 1984 mockumentary This Is Spinal Tap, whose satirical portrayal of rock excess became one of the most influential comedies in music history and a touchstone for heavy metal culture worldwide.

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.