This paper seeks to empirically evaluate the association of decentralization of education systems and student achievement. It employs PISA (2015) data to perform multilevel analysis for each and every participating country. Decentralization effects are estimated on the imputed scores of mathematics after controlling for various student level and school-level covariates. Findings reveal an important pattern across the analyzed countries. The random intercepts models suggest that decentralization has no significant effect on student achievement. The results of this paper challenge the primary notions of advocating for decentralization in education systems for improving student outcomes. Based on the empirical evidence from a multitude of countries, this paper argues that decentralization could be more of a false promise and an ineffective prescription.