The Common European Framework of Reference for Languages Companion Volume (CEFR CV) emphasizes macro-functions of language (i.e., reception, production, interaction, and mediation). However, there seems to be little consensus on whether the macro-functions are commensurable with CEFR-based proficiency tests. This paper focuses on the Examination for the Certificate of Competency in English (ECCE), which is based on the CEFR and assesses high-intermediate level English proficiency. Specifically, the study explores the latent structure of the ECCE and its generalizability across groups (i.e., gender, age, and first language [L1]) to examine its construct validity, dimensionality of language proficiency, and commensurability with the CEFR macro-functions. The latent structure was examined through confirmatory factor analysis using performance scores from 9,700 test-takers. The results indicated that test-takers' performance on the ECCE could be best represented by a correlated three-factor model (i.e., reading/listening/lexico-grammar, writing, and speaking abilities). The correlated three-factor model also held irrespective of gender, age, and L1 (with the exception of vocabulary scores). Overall, the findings indicate that the correlated three-factor model is consistent with the constructs that the ECCE proposes to measure, is in line with the current multi-componential view of language proficiency, and is partly commensurate with the CEFR macro-functions.