<p>The ingroup advantage refers to the phenomenon of emotions being more accurately recognised when expressors and perceivers share the same cultural background. Though well-documented in studies using posed facial expressions, whether the in-group advantage generalizes to spontaneous expressions remains unclear. This pre-registered study examined cross-cultural emotion recognition using dynamic posed and spontaneous expressions in a balanced design. Perceivers from the Netherlands (<i>N</i> = 762) and China (<i>N</i> = 738) judged emotions from facial expressions produced by Dutch and Chinese expressors in a forced-choice emotion recognition task. Contrary to our hypothesis, we did not find a mutual ingroup advantage. Instead, we found a Decoder and an Encoder effect for both posed and spontaneous expressions. Specifically, Dutch Perceivers outperformed Chinese Perceivers in recognising both Dutch and Chinese emotional expressions (the Decoder effect), while Chinese emotional expressions were better recognised than Dutch expressions by both Chinese and Dutch Perceivers (the Encoder effect). Bayesian analyses confirmed robust evidence for these effects. These findings challenge the robustness of the ingroup advantage and highlight the importance of using ecologically valid stimuli in the study of nonverbal emotional communication.</p>