Early studies of genetic variation in the Red-Bellied Newt, Taricha rivularis, revealed only small amounts of genetic differentiation among populations. However, these studies sampled only a limited portion of the range of the species. To address this gap in our understanding, we measured genetic variation in T. rivularis using allozymes (45 loci) and mitochondrial DNA (mtDNA) cytochrome b sequences (366 base pairs). With the goal of surveying broadly for levels of genetic variation, four populations were sampled, three in the southern portion of the range, and one at the northern end of the range. Allozyme divergence throughout T. rivularis was low, with a maximum Nei's genetic distance of D_N  =  0.039. MtDNA haplotype diversity was similarly low, with only two haplotypes differing by a single base pair recovered among the four populations. Relative to other salamander species in western North America, T. rivularis shows weak genetic differentiation among populations.