This study focuses on evaluating the internal control system in commercial companies in Cuenca and proposing improvement strategies based on the results. The methodology adopted combines qualitative and quantitative approaches, using an instrument based on the COSO methodology. This questionnaire consists of 63 closed questions, to collect information about the 5 components of internal control, the sample was made up of 14 companies. The evaluation was divided into four phases: I. Planning, II. Execution, III. Results and IV. Improvement plan. The results are positive for trust, in the system and for its components with ranges between 76% and 85%. While trust in supervision or monitoring was evaluated as moderate. Finally, the identified weaknesses were addressed by drawing up an improvement plan in some companies belonging to the studied population.