Montana records
Common Garter Snake in Montana
HarmlessThamnophis sirtalis

Yes. The Common Garter Snake has been recorded in 30 Montana counties. It is non-venomous (harmless). Slender body with three light stripes running the length of a darker back.
Montana counties with Common Garter Snake records
30 listedSee the full Common Garter Snake profile or all snakes in Montana.