We conducted the first population-based impact assessment of a financing policy introduced in Burkina Faso in 2007 on women's access to delivery services. The policy offers an 80 per cent subsidy for facility-based delivery. We collected information on delivery in five repeated cross-sectional surveys carried out from 2006 to 2010 on a representative sample of 1050 households in rural Nouna Health District. Over the 5 years, the proportion of facility-based deliveries increased from 49 to 84 per cent (P<0.001). The utilization gap across socio-economic quintiles, however, remained unchanged. The amount received for all services associated with births decreased by 67 per cent (P<0.001), but women continued to pay on average 1423 CFA (\[euro]1=655 CFA), about 500 CFA more than the set tariff of 900 CFA. Our findings indicate the operational effectiveness of the policy in increasing the use of facility-based delivery services for women. The potential to reduce maternal mortality substantially has not yet been assessed by health outcome measures of neonatal and maternal mortality.