This paper estimates the impact of private education on the academic achievement of low-income students in Chile. To deal with selection bias, we use propensity score matching to compare the test scores of reduced-fee paying, low-income students in private voucher schools to those of similar students in public schools and free private voucher schools. Our results reveal that students in fee-charging private voucher schools score slightly higher than students in public schools. The difference in standardized test scores is approximately 10 points, a test score gain of 0.2 standard deviations. We find no difference in the academic achievement of students in the private voucher-fee charging treatment group relative to their counterparts in free private voucher schools. Variables used in the analysis are appended. (Contains 13 tables and 31 footnotes.) [Funding for this research was provided by Fondecyt, the Fulbright Commission, and PBCT-CONICYT Project CIE-05.]