Middletown's Sleepy Hollow deal in classic heavy and power metal with a sound shaped by the genre's foundational era, having been active since 1992. Their work reflects the anthemic, riff-forward approach that drove American power metal before the genre's later stylistic proliferation.

Boston's Slight of Mind have been working traditional heavy metal territory since 2000, grounding themselves in the genre's classic structures and melodic sensibility within a city better known for its hardcore heritage. Their two-decade run reflects a commitment to straightforward metal craft in the New England underground.

Philadelphia's Slik Helvetika carry the torch for classic heavy metal in a city whose metal underground has historically favored extremity, bringing a traditional approach to riff-writing and song structure since 2016. Their work sits in the lineage of hard-hitting metal that emphasizes hooks and raw energy over stylistic novelty.

Rochester's Slikk Wikked mix the swagger of classic heavy metal with the punch of thrash, delivering a sound that nods to the harder-rocking end of both traditions since their 2016 start. Their hybrid approach keeps the energy high while leaving room for the melodic instincts that separate heavy metal from pure aggression.

Los Angeles' Slizard bring a reptilian swagger to heavy metal since their 2021 formation, working within the genre's traditional structures in a city whose underground supports both massive arena acts and basement-level metal diehards. Their sound channels the raw, riff-forward approach that has always been heavy metal's backbone.

Slyther is a heavy metal band from Las Vegas, Nevada, formed in 2023, drawing on classic metal traditions to craft a straightforward and hard-hitting sound in the early stages of their career.

Smaug is a Colorado Springs heavy metal band formed in 2020, blending doom-laden tempos with thrash metal punch and classic heavy metal structure, named after the legendary dragon of Tolkien's Middle-earth.

Smithereenz is a heavy metal and hard rock band formed in 2022, delivering energetic guitar-driven music rooted in the melodic and accessible end of the heavy metal spectrum.

Smoke Healer is a stoner and heavy metal band from Hebron, Kentucky, formed in 2015, blending the slow, fuzz-laden grooves of stoner metal with traditional heavy metal riffing and a hard rock foundation.