This paper investigates the effects of user-centric, security, and system characteristics and the moderating effects of gender on behavioural intention to use mobile payments (m-payment) services in Tanzania. The study extended the Technology Acceptance Model (TAM) to better explain and predict the users’ intentions to use m-payment services. A questionnaire survey was conducted with 292 m-payment users in Morogoro and Dar es Salaam, Tanzania. The study used structural equation modeling and multi-group analysis for data analysis. The study found that compatibility, social influence, and m-payment knowledge determined perceived usefulness, while m-payment knowledge, trust and compatibility predicted perceived ease of use of m-payment services. Moreover, perceived ease of use determined perceived usefulness, and perceived usefulness and personal innovativeness in turn, had positive effects on the behavioural intention to use m-payment. There were gender differences on the behavioural intention to use m-payment. The effect of compatibility and personal innovativeness on perceived ease of use, and the influence of ease of use on behavioural intention were moderated by gender such that it is more significant for men more than women. The effects of social influence on perceived usefulness were stronger for female more than their male counterparts. The paper provides empirical findings for mobile service providers to improve their marketing plans, and development of new applications in the Tanzanian culture or other countries with similar conditions.