This randomized, split-site, within-participant controlled clinical study evaluated the efficacy and safety of a single session of autologous nanofat injection as an adjunct to narrowband ultraviolet B (NB-UVB) phototherapy in 20 adult patients with stable vitiligo. In each participant, one vitiligo site received autologous nanofat injection followed by NB-UVB phototherapy three times weekly for 3 months, while a comparable site received NB-UVB phototherapy alone. Treatment response was assessed by standardized photography performed by a blinded dermatologist, with evaluation of the onset and percentage of repigmentation, patient satisfaction, and treatment-related adverse effects.