Abstract The eastern red-backed salamander (Plethodon cinereus) is one of the most abundant vertebrate species in the forests of eastern North America. It is considered as an important species for ecological processes. Two phenotypes most commonly coexist in most populations, but in different proportions: the red-backed (striped) and lead-backed (unstriped) morphs. Recent large-scale studies suggested that both color morphs of P. cinereus occur in and beyond the species’ current northern range. The presence of lead-backed morphs in this area would contradict some previous studies that link the lead-backed morph with warmer conditions. To verify this hypothesis, we conducted inventories in the boreal forest of northwestern Quebec (Canada), outside or at the edge of the species’ known range, where temperatures are among the coldest encountered by this species. We documented 11 sites with the lead-backed morph, including 5 sites in the Parent area that fill a large gap in the species’ known distribution. Among the latter, we found 3 distinct populations in which the lead-backed morph reached frequencies of 43%–96%. These occurrences of P. cinereus are noteworthy given the harsh climatic conditions that prevail throughout the year and the recurrence of large-scale disturbances in these far-north forests. Our findings also agree with the mounting evidence that variation in color morph frequency is not related only to temperature or shifts in climate.