The use of self-regulated learning (SRL) strategies such as planning, goal-setting, monitoring, evaluating, and reflecting on ways to improve learning typically involve print-based literacy skills. Beginning adult English as a second language literacy learners (BELLs) who have had few prior experiences with formal, school-based learning are in the process of developing the formal SRL strategies associated with effective classroom learning. The use of portfolios in the classroom has been found to contribute to the development of both literacy and SRL strategies; however, investigations of BELLs’ portfolio use and SRL are scarce. To address this gap, 118 BELLs from 23 different classes were individually interviewed to investigate their experiences with and perceptions of portfolio use and assessment in their task-based language and literacy classes. Bi/multi-lingual interpreters conducted, transcribed, and translated the interviews into English. Students’ responses regarding the purpose of portfolios, the processes involved in using portfolios, their attitudes towards portfolios, and the influence of portfolios on their learning were thematically analyzed for evidence of SRL. Results revealed that (a) BELLs’ attitudes towards portfolios were generally positive in that portfolios helped them to organize their work for later review and allowed them to see their improvement, and (b) BELLs’ emergent understanding and use of portfolios as a tool for SRL was influenced by the high levels of teacher-regulation and the summative use of portfolio results for advancement in these classes. Findings are discussed in regard to the role of portfolios in developing SRL and their practical implications for literacy instruction.