[2] The distribution of Chiton magnificus ranges along the Pacific coast of South America from Cape Horn in Chile[3] to San Lorenzo Island in Peru.

[2] Although there are old claimed records of this species from the Galápagos Islands, these are now considered incorrect.

[2] This species is found in places with strong current along rocky coasts, including pools.

[2] It can be found at depths of 0–31 m (0–102 ft),[4] but in northern Chile it appears to be restricted to subtidal areas.

Although relatively uncommon, it is one of the few commercially important chitons in its range, others being the even larger, up to 23 cm (9.1 in), spiny Acanthopleura echinata and the smaller, up to 4.5 cm (1.8 in), brownish Chiton granosus.