The current study investigates the CEFR-based self-assessment implementations in English as a foreign language (EFL) classes in secondary education in Türkiye. The study adopted a qualitative research design, and the data were collected via document analysis, an interview form, and an observation checklist. The results revealed an incongruity between theory and practice regarding the CEFR-based self-assessment implementations in 9th grade EFL classes; the CEFR-based self-assessment was provided in the coursebook through 'can do' statements at the end of each unit in the 'Check Yourself ' parts. However, the compatibility of these items with the EAQUALS Bank of Descriptors as Checklists was relatively low. In addition, the study revealed that the participating teachers favoured self-assessment implementations in their classes. However, they did not implement the self-assessment parts upon completing units in real EFL class contexts.