Teacher well-being is a psychological asset for educators, often associated with job engagement and retention. However, sophisticated measures to comprehensively assess teacher well-being are still under investigation. This study explores the factor structure and cross-country comparability of the Teacher Subjective Wellbeing Questionnaire (TSWQ) among 393 early childhood education teachers from four European countries. Exploratory and confirmatory factor analyses generally supported the TSWQ's proposed dimensionality, identifying teaching efficacy and school connectedness as two distinct latent factors, along with indications for the existence of a general, higher-order factor. Additionally, measurement equivalence was established at all levels across the four countries. Discriminant validity analyses highlighted culturally specific nuances in the relationship between teacher well-being and burnout. The findings underscore the TSWQ's potential to advance theoretical and methodological research on teacher well-being and broaden the instrument's applicability across diverse educational settings.