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Surface ligands are often used to improve perovskite solar cells (PSCs). Here, a series of surface ligands with varying dipole moments are applied at the methylammonium lead iodide (MAPbI₃)/C₆₀ interface to vary the energy-level alignment. All investigated surface ligands improve PSC performance, with 4-fluorophenethylammonium iodide (FPEAI) displaying the greatest improvement. Transient absorption and reflectance measurements show similar recombination dynamics in all ligand-treated MAPbI₃/C₆₀ bilayer films. Transient photovoltage measurements also show similar recombination lifetimes at similar charge-carrier densities; however, differential capacitance measurements indicate that FPEAI shifts the differential capacitance curve to higher voltages. In situ ultraviolet photoemission spectroscopy measurements show that the interfacial energy gap at the MAPbI₃/C₆₀ interface increases from 1.19 eV …