This study investigates the functions of the translingual practices performed by young learners and their teachers in primary school CLIL and EFL contexts. We also aimed to explore if differences in translanguaging purposes existed between both educational programs. 22 7-year-old students from the 2nd year of primary education and their EFL and CLIL science teachers took part in the study. Participants belonged to a public school from the city of Alcora, in the Valencian Community (Spain), which offers three teaching languages (Catalan, Spanish, and English). Classroom observations and video-audio recordings were conducted in 8EFL (6 hours) and 8 CLIL lessons (6 hours). Data was transcribed and analysed employing two taxonomies that we have adapted, Sampson’s (2012) and Sahan and Rose’s (2021) classifications of language use. Qualitative data was examined through deductive and inductive analytical approaches. Quantitative data was analysed using the SPSS programme. Findings indicate that translanguaging was employed by participants in both contexts to accomplish particular teaching, learning, and communicative functions. However, translanguaging episodes were more frequent in EFL than in CLIL. Results from several Pearson’s chi-square tests and post hoc Bonferroni adjustments demonstrated differences in specific subfunctions of translanguaging between CLIL and EFL settings, dealing with certain aspects of students’ metalanguage and teacher’s content transmission and classroom management. This study suggests the adoption of a more multilingual approach in early language and content learning, as well as the need for teacher training on the use of effective translanguaging strategies.