Integrated soil fertility management (ISFM) has been promoted by research and philanthropic organizations as well as governments in an attempt to increase crop yields and improve livelihoods of smallholder farmers in Africa. As this has largely been a continent-wide initiative, it is surprising that there is still scant information on its impact on crop yields and household income. This paper uses a counterfactual model to assess ISFM impact on yields and total household incomes using farm household data from Tamale (northern Ghana) and Kakamega (western Kenya).