AbstractFor decades quaternary ammonium compounds (QACs) have served as main component of a top antiseptic and disinfectant compositions. Among them, bis‐QACs are the most prominent and effective class of biocides. Although mono‐QACs still dominate the antiseptic market, their activity against Gram‐negative bacteria is largely inferior to bis‐QACs. Moreover, the new wave of bacterial resistance during the COVID‐19 pandemic is threatening the efficiency of popular antiseptics. Therefore, the requirement for novel biocides is urgent. Reported here is a unified and simple two‐step synthesis to achieve novel biocide's architectures with aromatic linkers. Thus, a series of 14 bis‐QACs have been prepared using an Ullman‐type reaction following by N‐alkylation. The most prominent compounds showed strong bioactivity against a panel of nineteen microbial pathogens, multi‐resistant bacterial ESKAPEE strains, fungi and biofilms, including strains, which acquired resistance during COVID‐19 in 2021. Moreover, significant improvements in antibiofilm action were observed, where bis‐QACs 5 c and 6 a outperformed gold standard pyridinium antiseptic octenidine. These findings will serve as a good basis for further studies of bis‐QACs architectures as highly effective biocides.