Teachers' beliefs, conceptualised as heuristics encompassing perceptions and ideologies regarding aspects of their profession, strongly influence their practices. Grounded in this perspective, this study investigated teachers' beliefs and perceived practices in the context of teaching English as foreign language (EFL) to immigrant students in Israeli schools. Utilising a mixed-methods approach, data were collected from 153 teachers via questionnaires and semi-structured interviews. Two major sets of beliefs emerged in the data, aligning conceptually with two of Ruíz's orientations to language planning and multilingual societies: "multilingualism as a resource," and "multilingualism as a right," reflected in supporting special accommodations for immigrant students. These beliefs were found to be significantly related to teachers' reported practices. Certain factors, especially teachers' personal biography as immigrants and the particular school contexts, have been identified as predictors of teachers' beliefs about teaching immigrant students in the EFL classroom. Results further indicate insufficient professional knowledge about the unique conditions and challenges confronted by immigrant students while acquiring an additional language. Recommendations are made regarding professional development programmes for teachers within the framework of 'language as resource'.