The language used in dubbing has often been described as contrived, stilted and, in general, unidiomatic. This paper sets out to study phraseological translation as a parameter to assess the idiomaticity of the Spanish dubbing language. The corpus analysed consists of a number of transcripts of the aired episodes of the American TV series Friends and their dubbed versions in Spanish. The article offers both a quantitative and qualitative analysis of the corpus under study. Finally, it provides a description of the unidiomatic features detected in the dubbed text as well as a tentative explanation of their origin.