Two [N···I⁺···N] halogen-bonded dimeric capsules using tetrakis(3-pyridyl)ethylenecavitands with different lower rim alkyl chains are synthesized and analyzed in solution and the gas phase. These first examples of symmetrical dimeric capsules making use of the iodonium ion (I⁺) as the main connecting module are characterized by ¹H NMR spectroscopy, diffusion ordered NMR spectroscopy (DOSY), electrospray ionization mass spectrometry (ESI-MS) and ion mobility-mass spectrometry (TW-IMS) experiments. The synthesis and effective halogen-bonded dimerization proceeds through analogous dimeric capsules with [N···Ag⁺···N] binding motifs as the intermediates as evidenced by the X-ray structures of (CH₂Cl₂)₂@[3a₂∙Ag₄∙(H₂O)₂∙OTs₄] and (CH₂Cl₂)₂@[3a₂∙Ag₄∙(H₂O)₄∙OTs₄], two structurally different capsules.