We identify the impact of the 2003 Kenyan Free Primary Education (FPE) programme on gender imbalances in the number of students graduating from primary school and achievement on the primary school exit examination. Our identification strategy exploits temporal and spatial variations in the pre-programme dropout rates between districts in a difference-in-differences strategy. We find that the programme boosted primary school completion rates of both boys and girls, but had a larger effect for boys, thereby increasing the gender gap in graduation. Additionally, the programme led to a widening of the achievement gap in government schools. Overall, FPE increased educational access, but did not close gender gaps, suggesting that complementary programmes that specifically target girls may be necessary to reduce these gaps.