AbstractA new additional benzothiazole (BT) acceptor has been introduced into metal‐free organic dyes (MCG1–MCG4) to construct donor–acceptor–π–acceptor (D‐A‐π‐A) architecture with the systematic replacement of diheteroanthracene donors and heteroaromatic π‐bridge components. BT not only facilitates effective electron transfer from the donor to the anchoring group, but also lowers the band gap. The planarity of the sensitizers induces J aggregation on TiO2, causes the redshift on TiO2, and enhances the light‐harvesting efficiency up to λ=750–800 nm. Transient absorption spectroscopy and electrochemical impedance spectroscopy have been used to understand the trends in short‐circuit current (Jsc) and open‐circuit voltage (Voc). Dye MCG4 showed a superior efficiency of 6.46 %. DFT has been complemented with experimentally determined photoelectrochemical properties. These molecules are new and support π‐bridge extension with BT for better performance of D‐A‐π‐A organic sensitizers.