A 20‐item scale to measure general impulse buying tendency was developed and validated in two studies. The scale includes cognitive aspects (e.g. lack of planning and deliberation) and affective aspects (e.g. feelings of pleasure, excitement, compulsion, lack of control, regret). The scale correlated significantly with reported purchase frequencies of typical impulse products and number of recent impulse purchases. Impulse buying tendency was found to be related to personality‐based individual difference measures, including the Big Five. Cognitive and affective facets of impulse buying tendency were both related to extraversion. The cognitive facet was inversely related to conscientiousness, personal need for structure, and need to evaluate. The affective facet was related to lack of autonomy and action orientation. The results suggested that impulse buying tendency has a strong basis in personality. Copyright © 2001 John Wiley & Sons, Ltd.