Long COVID is a multisystemic condition that complicates diagnosis due to the nonspecific and heterogeneous nature of its symptoms. The most frequently reported symptoms are fatigue, brain fog, cognitive impairment, insomnia, dizziness, and vertigo. Some symptoms may persist for years, and it is unclear whether they will become permanent. Long COVID substantially impacts affected individuals by impairing their work performance, psychosocial well-being, and overall quality of life.The objective of this study was to evaluate cognition, balance, and retinal fundus findings in individuals with Long COVID compared with healthy controls.A cross-sectional study was conducted in the public healthcare network of the Northern Metropolitan Area of Barcelona, including 268 participants (201 with Long COVID and 67 healthy controls). Sociodemographic characteristics, substance use, comorbidities, and COVID-19–related clinical data were collected. Cognition was evaluated using a neuropsychological battery, while balance was assessed through posturography and retinal vascular involvement by retinography.Most participants were women (80.97%), with a mean age of 48.6 ± 9.5 years. Groups differed significantly in the clinical spectrum of the initial SARS-CoV-2 infection, BMI, and years of education. Long COVID patients showed greater cognitive impairment, with significant differences in the number of affected domains and in most cognitive domain scores (p ≤ 0.001), except for visuospatial and visuoconstructive functions. Balance dysfunction was more frequent in the Long COVID group than in controls (45.5% vs. 21.0%; p = 0.001). No significant differences in retinal findings were observed between groups.This study suggests that patients with Long COVID experience significant cognitive impairment. Language, visuospatial, and visuoconstructive abilities appear relatively preserved, whereas executive functions, attention, and memory are the most affected domains. Posturographic findings indicate that balance impairment is not attributable to dysfunction of a single system but rather reflects a generalized involvement of multiple systems contributing to postural control. Long COVID does not appear to cause detectable retinal alterations.These findings highlight the importance of a comprehensive understanding of the effects of Long COVID and underscore the need for targeted, multidisciplinary interventions.