Among 418 patients with polycythemia vera seen at our institution and in whom pruritus history was recorded, the presence of pruritus at diagnosis was documented in 131 (31%) and its absence in 287 (69%). Pruritus was less frequently reported by smokers (12% vs. 24%; P = 0.004) and diabetics (5% vs. 11%; P = 0.04). The presence of pruritus was associated with a lower rate of arterial thrombosis, both at diagnosis (8% vs. 17%; P = 0.01) and during follow-up (16% vs. 30%; P = 0.003). Multivariable analysis revealed that these associations were independent of other risk factors for thrombosis. High JAK2V617F allele burden clustered with pruritus (P = 0.002) but did not affect thrombosis rates.