Anion sensing behaviour of a quinoline-based derivative has been explored and is found to be selective towards HSO₄⁻ over a variety of anions including oxo anions. The sensing protocol has been suggested to proceed via a static emission quenching process which has further been supported by ¹H NMR, UV-vis and theoretical (DFT, TD-DFT) calculations indicating the formation of a hydrogen-bonded complex between the quinoline part of the receptor and HSO₄⁻.