This quantitative study established the best fit model for professional learning communities in public elementary schools with team effectiveness, school culture and community of inquiry as exogenous variables. This research used descriptive correlational research design employing survey method with 400 teachers in public elementary schools in Davao Region in the Philippines identified through stratified random technique. The adopted and modified questionnaires which were tested for content validity and reliability were administered either in-person or google forms. This descriptive and causal research used the following statistical tools to treat data; mean, standard deviation, Pearson product-moment correlation, linear regression, and structural equation modelling.Findings revealed very high level of team effectiveness, school culture, community of inquiry and professional learning communities. Moreover, the independent variables, team effectiveness, school culture, and community of inquiry showed significant relationship with the dependent variable, professional learning communities. The study also indicated that the three exogenous variables significantly predict the outcomes of professional learning communities. It also generated 5 models to determine the best fit model. Model 5 successfully passed the conventions of a reasonable fit. Hence, Model 5 is the best fit model for professional learning communities. In the model, several indicators were retained; team effectiveness is defined through purpose and goals, problem solving, and skills and learning, while school culture through teacher collaboration and collaborative leadership, and community of inquiry through cognitive, social, and teaching presences.