The purpose of this research was to test novelty as a candidate basic psychological need according to the inclusion criteria established within basic psychological needs theory (BPNT). Two cross-sectional studies with 303 (Mage = 33.50, SD = 12.95; 58.41% female) and 598 (Mage = 35.47, SD = 11.89; 54.18% female) Spanish adults were conducted in physical exercise and general life contexts with the following aims: (1) to analyze relations between novelty satisfaction/frustration and well-being outcomes; (2) to examine the mediating role of motivation (autonomous, controlled, and amotivation) in these relations; and (3) to study whether these associations held regardless of the importance participants attached to the need for novelty, and their level of openness to new experiences. In Study 1, satisfaction of the need for novelty positively and directly predicted autonomous motivation and vitality in physical exercise, beyond the three existing basic needs. It also indirectly predicted enjoyment and vitality through autonomous motivation. There was little evidence that importance ratings for need for novelty moderated these relations. In Study 2, novelty satisfaction positively predicted, and novelty frustration negatively predicted, vitality, life satisfaction, and meaning in life. Openness to experience strengthened the relations between novelty satisfaction/frustration and outcomes. A similar pattern of effects was found for the three basic psychological needs. Results provide preliminary support of novelty as an additional candidate need in BPNT.