Electron spin resonance (ESR) spectroscopic line shape analysis and continuous-wave (CW) progressive microwave power saturation experiments are used to probe the relaxation behavior and the relaxation times of charged excitations (hole and electron polarons) in meso-to-meso ethyne-bridged (porphinato)zinc(II) oligomers (PZnn compounds), which can serve as models for the relevant states generated upon spin injection. The observed ESR line shapes for the PZnn hole polaron ([PZnn](+center dot)) and electron polaron ([PZnn](-center dot)) states evolve from Gaussian to more Lorentzian as the oligomer length increases from 1.9 to 7.5 nm, with solution-phase [PZnn](+center dot) and [PZnn](-center dot) spin spin (T-2) and spin lattice (TO relaxation times at 298 K ranging, respectively, from 40 to 230 ns and 0.2 to 2.3 mu s. Notably, these very long relaxation times are preserved in thick films of these species. Because the magnitudes of spin-spin and spin lattice relaxation times are vital metrics for spin dephasing in quantum computing or for spin-polarized transport in magnetoresistive structures, these results, coupled with the established wire-like transport behavior across metal-dithiol-PZN(n)-metal junctions, present meso-to-meso ethyne-bridged multiporphyrin systems as leading candidates for ambient-temperature organic spintronic applications.