Collective self-consumption is called to be a crucial part of the current energy transition. In addition to the advantages of individual self-consumption, the possibility of improving economic feasibility exists. This paper shows how matching production and consumption loads increase the rate of self-consumption. Still, how the electricity is distributed among a renewable energy community’s prosumers would reduce the total costs of self-consumed energy. Possible criteria for the allocation of the generated electricity among shareholders are analysed. The study also evaluates the use of static and dynamic distribution coefficients, observing their results and applicability and sorting them to maximise self-consumption participants’ savings. The results are questioned against them and a reference scenario without shared self-consumption installation. As the exploitation of renewable energy for self-consumption is closely linked to the energy market and regulations, the analysis is based on a territorial case study. It is shown that the highest savings occur when electricity is allocated following distribution coefficients that consider the customer’s energy consumption better than investment participation or contracted power, even when the compensation of surpluses is added. These criteria can accomplish technical and economic objectives and are introduced in regulations that foster the requested changes in consumers’ behaviour and prosumers for sustainability.