Two classes of widely studied luminescent metal complexes are octahedral d6 (i.e., Ir3+) and square planar d8 (i.e., Pt2+) polypyridyl complexes, which have distinctly different photophysics and photoreactivity. In this study we report a series of d6-d8 IrIII-PtII hybrid complexes arising from coordination of metalloligands IrL2(benzene-1-thioether-2-thiolate) or Ir(L)2(benzene-1,2-dithiolate) anion [L = 2-phenylpyridine (ppy), 2-(2,4-difluorophenyl)pyridine (dfppy), or 1-phenylisoquinoline (piq)] to Pt(terpy)2+ (terpy = 2,2':6',2″-terpyridine). X-ray crystal structures of the Ir-Pt complexes show the IrL2 and Pt(terpy) chromophores are cofacially oriented with interplanar distances of 3.268-3.442 Å. Density functional theory (DFT) calculations show that the highest occupied molecular orbital and the lowest unoccupied molecular orbital are localized in the IrL2 and the Pt(terpy), respectively. All the complexes display a low-energy absorption band (λmax = 460-534 nm, εmax = (0.75-2.13) × 103 M-1 cm-1), which is attributed to interchromophore-charge-transfer (ICCT) transition, according to time-dependent DFT calculations. The 3ICCT excited state is emissive, giving long-lived phosphorescence that reaches as low as near-infrared (λmax = 668-710 nm, τ = 0.17-0.79 μs).