(Difluoro)methoxyoxo iodine(V) (IF2(O)OCH3), the methyl ester of the unknown difluoro iodic acid (IF2(O)OH), was obtained by the reaction of methoxytrimethyl silane with iodine pentafluoride. IF2(O)OCH3 crystallizes orthorhombic in the space group Pbca with a = 7.605(1) Angstrom, b = 7.360(1) Angstrom, c = 15.017(1) Angstrom, and eight formula units per unit cell. The final R indices [I > 2 sigma>(*) over bar * (I)] are RI = 0.0264 and wR2 = 0.0516. Additionally, IF2(O)OCH3 was characterized by its vibrational spectra and quantum mechanical calculations were performed.