A general belief is that Mobile Money (mMoney) has the catalytic effect of spurring mCommerce growth and driving financial inclusion in developing nations like Nigeria. In Nigeria, mMoney service is certainly a new financial service innovation in the country, and as a result critical issues surrounding its early critical mass adoption, including its perceived usefulness, remain largely opaque. In this paper, our aim was to explore factors influencing perceived usefulness of mMoney by using the extended technology acceptance model (TAM) as the theoretical underpinning of our work. This work is based on a usable sample of 127 respondents from two major cities in Nigeria. Overall, the study's results indicate that perceived regulator assurance, service affordability, convenience, proximity to the nearest bank branch, and worry over ease of use are significant predictors of mMoney perceived usefulness. The work helps shed new insights about the significant factors that are closely related to the consumer's perception of the relevance of mMoney services (to his/her financial needs). In sum, the study is an initial step to addressing the issue of perceived usefulness of mMoney service, including its pivotal importance to laying a solid foundation for mCommerce growth in Nigeria and similar sub-Saharan African (SSA) countries.