Abstract Premise Little is known about the ability of individual species to grow successfully outside of their realized niche. Here, the vitality of two epiphytic bryophyte and two epiphytic lichen species were assessed in their fundamental and realized niches in the Pacific Northwest coniferous forest at low, mid, and high elevations. Methods Two lowland epiphytic bryophyte species (Frullania nisquallensis, Neckera douglasii) and one lowland epiphytic lichen species (Usnea longissima) were transplanted to sites at mid and high elevations. One high-elevation epiphytic lichen species (Hypogymnia rugosa) was transplanted to mid and low elevations. Results The fundamental and realized niches of F. nisquallensis and U. longissima are similar, and they can both survive outside of their realized niches. For N. douglasii, dispersal limitations could shape its distribution along elevation and local microclimate conditions could be important for its vitality. Conclusions Certain bryophyte and lichen species can survive outside of their realized niches, information that can contribute to knowledge about species niches along elevational gradients. Future studies should focus on cryptogam species interactions in a changing climate.