<p>Economic Evaluation (EE) is increasingly used to inform the decision-making of various health care systems about which health care interventions to fund with the available resources. Until now, majority of cost-effectiveness analyses have been performed with Microsoft Excel (ME). Today, the trend is to use software that can improve the decision-making model and that can resolve complex problems, as well as ensure reproducibility and transparency. </p><p>The intention of this tutorial paper is not to show the “best” way of developing decision models in R, but to provide two different codes described in a step-by-step guide on how to implement a Markov model, with an explanation to help beginners in modeling (e.g., health economists new to R) and MS Excel users and to switch to R without having any great knowledge of programming with R. </p><p>This paper is offered to facilitate the wider use of R to implement decision-making models.</p>