Arctic soils store vast amounts of frozen carbon that will thaw, fueling microbes that produce carbon dioxide and methane greenhouse gases. We compared methane producing and oxidizing activities in incubated soils and permafrost of Arctic tundra to improve estimates of net emissions. The methane oxidation profile in these soils differs from temperate ecosystems: maximum methane oxidation potential occurs in suboxic soils and permafrost layers, close to the methanogens that produce methane.