Geoffroy's cat (Leopardus geoffroyi) is a small Neotropical felid whose social behavior remains poorly understood. We used simultaneous radiotelemetry (4 males and 3 females) and camera trapping to examine the spatial structure and dynamics of a population of this species in the Brazilian pampas (part of the Uruguayan Savannah ecoregion), including assessment of interindividual genetic relatedness. Home ranges (HRs) and core areas of males were larger than those of females. Males were significantly heavier than females, and linear regression analyses indicated that body mass of males significantly influenced HR size, whereas the relationship was not significant for females. When we performed a joint analysis comparing our data to those reported previously for other study sites, we observed the same patterns. We detected extensive HR and core area overlap among most of our monitored individuals, with no clear sex-based pattern. Moreover, our molecular data indicated that most of the sampled individuals were unrelated, and that the levels of HR and core area overlap were not significantly influenced by genetic relatedness. These results suggest that some interindividual tolerance and relaxation in territoriality may occur in Geoffroy's cat. We detected only minor changes in HR and core area size and overlap between seasons, indicating that the spatial structure we observed was temporally stable. On a broader perspective, our cross-site comparisons illustrate the usefulness of performing multiple ecological studies employing comparable methods at different locations to better understand the ecology of wild felid populations.