Summary: New polyindolocarbazoles (PIC) and polydiindolocarbazoles (PDIC) have been synthesized using Yamamoto polymerization reaction. These polymers have been investigated by cyclic voltammetry, UV‐Vis‐NIR spectroelectrochemistry, electrochemical quartz crystal microbalance, in situ electron spin resonance, and in situ conductivity techniques. Two redox oxidation processes, each involving one electron per repeat unit, produce radical cations (free or π‐dimerized) and dications. Each one‐electron redox process is generally split into two due to the stabilization of mixed‐valence states. The oxidative charge is delocalized over the polyconjugated backbone with neutral‐polaron conductivities in the range 0.002–0.04 S · cm?1 and polaron‐bipolaron conductivities in the range 0.04–0.5 S · cm?1. Conductivities are higher when nitrogen atoms are involved in the conjugation pathway.
