Uganda is the second largest contributor of total malaria cases in East and Southern Africa. Domestically, the burden of malaria is enormous and persistent (high morbidity, mortality, and economic loss). Among other strategies, the government has proposed large-scale Indoor Residual Spraying (IRS) intervention as a major component of current malaria control efforts, and recently, the political leadership voiced solidarity towards fighting malaria through the “Mass Action Against Malaria” campaign. This paper was motivated by the paucity of evidence on requisite financial resources to fund country-wide and phased IRS implementation. Additionally, given that the economy is highly resource constrained and is faced with innumerable competing development priorities and needs, it is imperative to explore low-cost options for IRS implementation. Therefore, this paper was aimed at analysing the costs of the country-wide roll out of IRS under different IRS delivery models, the cost implications of implementing IRS in a phased manner, and identifying cost-minimization strategies. We used the latest Uganda National Household Survey, market price data, and data from IRS pilot districts.