Tert-butyl carbazole-based self-assembled monolayers (SAMs) are promising hole-transport layers (HTLs) for inverted perovskite solar cells (PSCs) but suffer from poor wettability toward perovskite precursor solutions. Here, a self-assembled bilayer (SAB) composed of a tert-butyl functionalized CBZC2 SAM and a conjugated polyelectrolyte wetting interlayer (PFN-Br) is employed as the HTL in CsI₀.₀₅FA₀.₉₂MA₀.₀₈Pb(I₀.₉₂Br₀.₀₈)₃ PSCs. The bulky tert-butyl group suppresses molecular aggregation, enhances hole extraction, and reduces interfacial recombination. As a result, CBZC2/PFN-Br-based devices achieved a power conversion efficiency of 24.1% with a fill factor of 81.5% and retained 96% of their initial efficiency after 500 h of maximum power point tracking, demonstrating excellent efficiency and stability.