In social interactions, emotional biases can arise when the emotional state of oneself and another person are incongruent. A person’s ability to judge the other’s emotional state can then be biased by their own emotional state, leading to an emotional egocentric bias (EEB). Alternatively, a person’s perception of their own emotional state can be biased by the other’s emotional state leading to an emotional altercentric bias (EAB). Using a modified audiovisual paradigm, we examined in three studies (n = 171; two (...) online & one lab-based study) whether emotional biases can be considered traits by measuring two timepoints within participant and relating empathy trait scores to emotional biases, as well as the electrophysiological correlates of emotional biases. In all studies, we found a congruency effect, reflecting an EEB and EAB of small size. Both biases failed to correlate significantly within participants across timepoints and did not display significant relationships with empathy trait scores. On the electrophysiological level, we did not find any neural emotional bias effects in the time–frequency domain. Our results suggest that EEB and EAB effects are strongly task sensitive. Caution is warranted when studying interindividual differences in emotional biases using this paradigm, as they did not show significant test-retest reliabilities. (shrink)