A total of 586 members of an online market research panel completed the International Personality Item Pool (IPIP) Big Five personality inventory and were then offered one of three incentives (lower than normal, normal and higher than normal) to evaluate a new consumer product. Consistent with predictions based on equity theory, participants who were offered lower than normal incentives rated the product less favourably than those who were offered normal incentives. Contrary to predictions, participants offered higher than normal incentives did not rate the product more favourably than those who were offered the normal incentive. Respondents scoring high on Agreeableness, Conscientiousness, Openness and Extraversion rated the product more favourably than those who scored low on these dimensions. Implications for market research are discussed.