Blended language learning has recently experienced substantial growth, offering numerous potential benefits such as increased learning opportunities and personalization. However, digital inequalities persist, particularly affecting vulnerable groups like migrants with limited education. While the integration of technology in adult education may pose additional challenges for these groups, online learning paradoxically holds the promise of enhancing their basic skills. This study addresses this apparent contradiction, focusing on blended learning in Dutch second language (L2) education in Flanders (Belgium) for L2 learners with emerging literacy and limited formal education, representing the most vulnerable subgroup of L2 learners. This group is referred to as LESLLA learners (LESLLA is an acronym for Literacy Education and Second Language Learning for Adults). Through a combination of a systematic literature review and a needs analysis of stakeholders, including LESLLA learners themselves, the study explores the benefits and challenges of blended learning for LESLLA learners. The study reveals that while many affordances and limitations for adult L2 learners in general also apply to LESLLA learners, the significance varies based on their characteristics, curriculum goals, and context. In order to realize the affordances, while also tackling the challenges, effective blended education for low-literate L2 learners requires (1) a thoughtful design of the blend, in which instructional design principles are integrated with didactic principles for L2 teaching; (2) effective teacher conduct; and (3) powerful policy of adult education centers. This paper outlines the characteristics of each component, offering insights to strengthen blended L2 learning experiences for LESLLA learners.