Over the last fifteen years, European countries have increasingly relied on competitive grants to allocate research funding, replacing the more traditional block funding model. Policymakers are interested in assessing the effectiveness of the grant funding model in producing impactful research. However, the literature aiming to quantify the effect of grants on the resulting research’s impact is scant. In the French context, we compare the impact of scientific articles resulting from the support of competitive grants from the main national funding agency with the impact of articles not supported by grants. We rely on publication acknowledgments to retrieve funding information and on citation data to assess the articles’ impact. We find that articles supported by competitive grants receive more citations than articles not supported by grants in the long run, while the difference is not statistically significant in the short run. We find heterogeneity in the effect of grant funding on citations across fields.