Despite government support to boost domestic production, tomato consumption in Ghana is heavily dependent on imports. Improved tomato seed varieties (ITSV) are considered inputs to increase productivity, but their contribution to household welfare is quite unknown. We examined the impact of ITSV adoption on household welfare in three agro-ecological zones of Ghana. Primary data was collected from a random sample of 508 tomato farmers using a semi-structured questionnaire. The study corrected for endogeneity bias in farmer adoption decisions using the multinomial endogenous switching regression model. The results show that the farmers' adoption of the improved varieties (Pectomech, Power Roma or both) was high and significantly influenced by sex, farm income, extension contact, credit access, perception of varietal characteristics (mainly yield), and farmers' residence in FSTZ, compared with the local variety (“Techiman”). Regarding household welfare, the adoption of Pectomech, Power Roma or both increased household expenditure and assets. Additionally, farmers gained more income by adopting Pectomech and both Pectomech and Power Roma. The findings suggest the need for research institutions like CSIR and the universities to step up the production of improved seed varieties with high-yielding capabilities and tolerance to pest, spoilage, and bad weather, while government and NGOs assist to increase farmers’ access to credit and extension services. The conceptual framework for the study is presented in Fig 3.4. Smyth (2004) defined a conceptual framework as a deep thinking or conceptualization of the processes or linkages or systems that can be used to simplify the understanding of a particular study. A conceptual framework tries to explain the linkages that exist among various concepts or variables used in the study. It starts from an inductive viewpoint to a deductive or from a simple to complex model below.