Results of Bayesian, maximum parsimony (MP), and neighbor joining (NJ) analysis of mitochondrial COII, 16S, and 12S gene DNA sequences and soldier morphology identified Chilean samples of a Reticulitermes species as the eastern subterranean termite, Reticulitermes flavipes (Kollar). All Chilean R. flavipes samples had identical gene sequences for all loci examined, suggesting a single geographic introduction. The combined DNA sequences for Reticulitermes santonensis Feytaud collected from France were almost identical to those of R. flavipes samples from Florida, which agreed with previous studies suggesting that R. santonensis is a junior synonym of R. flavipes. One unexpected finding was a R. flavipes sample collected from California that closely resembled the Chilean R. flavipes in their combined mitochondrial DNA sequences. We hypothesize that the Chilean R. flavipes may have been introduced from California or vice versa or that both Chilean and Californian R. flavipes may have the same origin in North America. Except for one sample from Florida (3% divergence), intraspecies variation of R. flavipes used in this study was <1%.