Empirical research on L3 teachers' beliefs has gained momentum in the last decade since teacher cognition is paramount for understanding teaching practices in multilingual settings. Yet, many of these works deal with experienced language practitioners (e.g. [Otwinowska, A. (2017). English teachers' language awareness: Away with the monolingual bias? Language Awareness, 26 (4), 304–324]) and focus on the impact of instruction about multilingual pedagogies (e.g. [Gorter, D., & Arocena, E. (2020). Teachers' beliefs about multilingualism in a course on translanguaging. System, 92 (102272)]. Less attention has been awarded to pre-service content teachers ([Portolés, L., & Martí, O. (2020). Teachers' beliefs about multilingual pedagogies and the role of initial training. International Journal of Multilingualism, 17(2), 248–264; Schroedler, T., & Fischer, N. (2020). The role of beliefs in teacher professionalisation for multilingual classroom settings. European Journal of Applied Linguistics, 8 (1), 49–72]) or to the effect of individual factors other than teacher training on their beliefs. To address this research gap, the present paper examines whether external and internal factors affect 121 teacher trainees' cognition about multilingualism in Infant and Primary education. Although no significant differences across groups are found, results depict a teacher's profile more inclined towards implementing multilingual policies.