Colon cancer is a leading cause of cancer related mortality. Until very recently the only existing options that medical oncologists had to treat metastatic colon cancer were a combination of chemotherapy, anti-EGFR and anti-angiogenic agents. We currently have the first proof that immune therapies could be an effective approach to battle colorectal cancers that carry a mismatch repair machinery deficient phenotype. It is expected that as our knowledge of the different mechanisms of immune-resistance grows, this therapeutic modality might soon be applicable to all patients. However, due to the continuous increase in the cost of oncological drugs, some treatment overheads may soon become prohibitive for many. In this review we will examine the current evidence related to this topic with the objective to provide the reader with concise but practical information about the potential role of immunotherapy in CRC.