Induced pluripotent stem cells (iPSC) are generated from fully differentiated somatic cells that were reprogrammed into a pluripotent state. Human iPSC which can be obtained from various types of somatic cells such as fibroblasts or keratinocytes can differentiate into cardiomyocytes (iPSC‐CM), which exhibit cardiac‐like transmembrane action potentials, intracellular Ca²⁺ transients and contractions. While major features of the excitation‐contraction coupling of iPSC‐CM have been well‐described, very little is known on the ultrastructure of these cardiomyocytes. The ultrastructural features of 31‐day‐old (post‐plating) iPSC‐CM generated from human hair follicle keratinocytes (HFKT‐iPSC‐CM) were analysed by electron microscopy, and compared with those of human embryonic stem‐cell‐derived cardiomyocytes (hESC‐CM). The comparison showed that cardiomyocytes from the two sources share similar proprieties. Specifically, HFKT‐iPSC‐CM and hESC‐CM, displayed ultrastructural features of early and immature phenotype: myofibrils with sarcomeric pattern, large glycogen deposits, lipid droplets, long and slender mitochondria, free ribosomes, rough endoplasmic reticulum, sarcoplasmic reticulum and caveolae. Noteworthy, the SR is less developed in HFKT‐iPSC‐CM. We also found in both cell types: (1) ‘Ca²⁺‐release units’, which connect the peripheral sarcoplasmic reticulum with plasmalemma; and (2) intercellular junctions, which mimic intercalated disks (desmosomes and fascia adherens). In conclusion, iPSC and hESC differentiate into cardiomyocytes of comparable ultrastructure, thus supporting the notion that iPSC offer a viable option for an autologous cell source for cardiac regenerative therapy.