A voting process allows the participation of citizens in the decision-making of a country. In Chile, the voting system is only face-to-face at polling places. The assignment historically did not consider the location (trip origins or residence) of voters, causing several mobility problems on election days. In 2022, the situation changed with the georeferencing of voters; therefore, an optimal allocation of polling places considering their initial location, the mobility of voters, and the supply of urban transportation is a critical factor. The research aims to propose a spatial allocation methodology for voters that considers the distance between voters and the closer polling place under a sustainable mobility approach. The optimization model of the location-allocation type analyzes the location of voters, the distance between polling places and voters, the capacity and number of polling places, and the public transport supply. The model is applied to San Miguel (commune) in Santiago, Chile, where the assignment of the electoral roll is modified based on the distance to the available and necessary polling places. The results are evaluated using transport modeling software, comparing the proposed scenarios with the current one. This methodology reduces travel times for voters by 59.83% and the traveled distance reduction from 4,000 to 1,800 meters with respect to the base scenario. A methodology such as the one proposed makes it possible to improve the tactical planning of voting processes regarding the supply of polling places, public transport supply, accessibility, and others.