The residential electricity demand were studied using the panel dataset of 21 cities and counties in Taiwan from 1998 to 2018. Observations were grouped and estimated separately for the urban and rural regions. Using the equality tests in the corresponding effects between the urban and rural models, the urban-rural gap of the electricity consumption was examined. The estimated results indicate that the effect of urbanization annually increased 0.52% of residential electricity demand in the urban regions, and decreased 0.02% of that in the rural regions. Considering the high replacement costs of appliances, low-income households tend to use the old and energy-inefficient ones that consume more electricity given the same electrical services. From 2011 to 2018, the decrease of the percentage of low-income households had reduced the electricity consumption by 0.68% in the rural regions.