Universal Primary Education (UPE) is one of the main objectives of development aid. However, very little empirical evidence of its effectiveness actually exists. Until very recently, the quality of available data was not sufficient to obtain robust results regarding the relationship between international aid and educational achievements. In this article, the latest, more disaggregated and more reliable data is used to study the relationship between aid to education and educational achievements. The focus here not only on educational variables in term of coverage, but also in term of equity and process. The year of Fast Track Initiative (FTI) endorsement is used as an original instrument to tackle the endogeneity problem of aid. Our results are very robust and indicate that aid to primary education has a strong effect on primary school enrollment and gender parity. A negative impact on repetitions rate is also indicated while no effect on the pupil teacher ratio can be observed. Diminishing return in the effectiveness of aid to primary education may also be highlighted. Finally, the governance variables do not appear to have an impact on this relationship.