Relative to their neutral precursors, higly charged multi-tritylium ions show typical downfield 1H-NMR shifts, whereas the corresponding phenylfluorenylium ions show upfield shifts. A Hückel basedmodel is presented that accounts for this contrasting behavior in terms of antiaromatic ringcurrent in the five-membered ring of the fluorenyl system with essentially null ringcurrents in the two six-membered