This paper examines the effect of uncertainty about the future on whether individuals select want options (e.g., junk foods, lowbrow films) or instead exert self-control and select should options (e.g., healthy foods, highbrow films). Consistent with the ego-depletion literature, which suggests that self-control resembles an exhaustible muscle, coping with uncertainty about what the future may bring reduces self-control resources and increases individuals’ tendency to favor want options over should options. These results persist when real uncertainty is induced, when the salience of naturally-arising uncertainty is heightened and when individuals are able to make choices contingent upon the outcomes of uncertain events. Overall, this work suggests that reducing uncertainty in a decision maker’s environment may have important spillover effects, leading to less impulsive choices.