Type 2 diabetes mellitus (T2DM) is mainly associated with impaired insulin secretion by the pancreatic β-cells, insulin resistance and elevated hepatic gluconeogenesis. Incretin based treatments for T2DM are now widely investigated and used. The incretin based therapies mainly include incretin hormones which are glucose-dependent insulinotropic peptides (GIP) and glucagon like peptide-1 (GLP-1) released from the endocrinal cells in the small intestine in response to food intake. The main function of GLP-1 is to induce insulin secretion and suppress glucagon secretion. This review describes the different formulation approaches for oral delivery of incretins and the limitations associated with this route of administration. We highlight the use of micro and nanosystems to efficiently deliver the incretins orally. Furthermore, we present several examples of the significant potential of these systems in pharmaceutical applications.