This paper presents a persuasive smart energy management system (PSEMS) which incorporates the peculiarities of the developing economies, for low/medium income earners, under the flat pricing regime. The PSEMS uses an algorithm based on mild modified intrusive genetic algorithm (MMIGA), with and without user preferences and considers grid status, while meeting the minimum demand criteria in terms of load allocation and cost optimization. Four budgetary conditions were used as case study. Results show that the dynamically generated demand (based on budget constraint) as obtained by PSEMS and the optimal dispatch as evaluated by MMIGA closely matches. Daily allocation efficiency in the range of 98.32–99.60% was obtained without users’ preference, while 98.76–99.67% was obtained with users’ preference, under the four budgetary conditions. The PSEMS allows the residential end user to make decisions regarding electricity consumption thus minimizing electricity bill and the use of electricity.