Stress may alter executive functioning by causing structural and functional changes to the brain. Sub-optimal decisions made under high levels of stress and anxiety may act as a mediator for stress-related health effects. We examined the effect of three personality traits–chronic stress, state anxiety, and trait anxiety–on updating working memory and feedback learning across 330 participants, using electroencephalography (EEG). We hypothesized a decrease in P300 (updating working memory) and reward positivity (feedback learning) amplitudes with increasing chronic stress and anxiety scores. The three personality traits were not correlated with reward positivity amplitudes. Additionally, chronic stress had no effect on P300 amplitudes. However, state and trait anxiety were negatively correlated with P300 amplitudes. Anxiety appears to impact working memory processes, and this effect was amplified with decreasing anxiety score quantiles to reflect the tails of the distribution. Our results are evidence of the beginnings of a correlation between anxiety and the neural correlates of decision-making, offering insight into anxiety-related adverse health outcomes.