The linear association between intelligence and openness has been estimated at r ≈ 0.20 to 0.30. However, little research has examined the possibility of a nonlinear effect between the two dimensions. Consequently, task-based intelligence and self-reported openness data were collected from 371 participants (UK community sample). We found that the association was nonlinear, i.e., the positive effect was no longer observed beyond an IQ of ≈ 105. Furthermore, across the 10 openness items, four evidenced positive, linear effects with intelligence, all of which were epistemic openness items. By comparison, several experiential openness items showed inverted U-shaped effects. It is concluded that, beyond relatively low to moderate levels of intelligence, general intelligence may be unrelated to global openness, especially if need for cognition is considered distinct from openness.