The objective of this observational study of consecutive patients hospitalized for cerebral venous thrombosis (CVT) was to determine the prevalence of post-CVT cognitive impairment and identify factors associated with this condition. Out of a total of 73 patients hospitalized for CVT, 52 were included in the study and 44 were assessed with a comprehensive neuropsychological battery. At the last outpatient visit (mean ± SD time since CVT: 22 ± 13 months), a standardized, neuropsychological assessment was administered. Cognitive impairment was defined as significant impairment (with a cut-off at the 5th percentile) in at least two of the cognitive domains tested in the neuropsychological battery or severe aphasia or cognitive disorders with MMSE score ≤ 17 out of 30. Cognitive impairment was observed in 16 patients (31 %; 95 % CI 18-43 %): 4 with major disability precluding comprehensive assessment (3 with severe aphasia, 1 with MMSE ≤ 17) and 12 with significant impairments in at least two cognitive domains. Determinants of long-term cognitive impairment were straight sinus involvement (OR 22.4; 95 % CI 1.79-278.95; p = 0.016) and the presence of parenchymal lesions on follow-up magnetic resonance imaging (OR 7.8; 95 % CI 1.40-43.04; p = 0.019). The sole predictor of failure to return to full-time employment was cognitive impairment (OR 21.0; 95 % CI 3.35-131.44; p = 0.001). Cognitive impairment persists in up to one-third of cases of CVT. It is more frequent in patients with deep CVT and persistent parenchymal lesions and is associated with failure to return to full-time employment.