Until now, there have been no reports of extrapair parentage in Tufted Titmice (Baeolophus bicolor). During 1995–1998, we used multilocus minisatellite DNA fingerprinting to estimate paternity and degree of relatedness in eight central Ohio broods of this socially monogamous species. Our results suggest a rather low rate of extrapair fertilization in the study population; three of 34 nestlings could not be attributed to the attending male. Of the three extrapair offspring, two represented the entire brood in a nest attended by their mother and a nonparental male that appeared to be a close relative of the mother.