<p>Metal-metal bonds between metal cations are ubiquitous in coordination complexes, whereas similar bonding characteristics between non-metal and metal cations are not. Here, we report an X-ray crystal structure of a centrosymmetric complex [Ag(<i>m</i>-O₃SCF₃)₂{(4MePyNO)₂I}]₂ (<b>1-AgI</b>), where the iodine(I) cation forms an unusual 3-centre 4-electron [O–I–O]⁺ halogen bond with two oxygen atoms from two 4-methylpyridine <i>N</i>-oxide (4MePyNO). The iodine(I) atoms from two [4MePyNO−I−ONPyMe4]⁺ cations, which, together with the two silver(I) atoms from the paddlewheel [Ag(<i>m</i>-O₃SCF₃)₂]₂²⁻ structure, establish two unique I⁺–Ag⁺ bonds at 2.863(2) Å. This bond length is characteristic of bimetallic coordination bonds such as Au⁺−Ag⁺ [2.8553(6) Å], Cu⁺−Ag⁺ [2.8616(9) Å], and Pt²⁺−Ag⁺ [2.8602(4) Å]. Density Functional Theory calculations unambiguously support the existence of the I⁺–Ag⁺ coordination bond between non-metal and metal cations in complex <b>1-AgI</b>.</p>