This paper presents the first detailed examination of the relationship between cognitive ability and charitable giving using both cross-sectional and longitudinal analysis. Data from a nationally representative, longitudinal survey of U.S. adults over age 50 indicated that higher cognitive ability-measured through a variety of cognitive tests-was associated with a higher probability of charitable giving, even after controlling for such intervening mechanisms as age, income, wealth, health, and education. This was true in comparisons both across different people at one point in time and within the same persons at different points in time. Understanding this relationship may affect the content and timing of appropriate charitable marketing approaches and help to explain other associations found in previous research on charitable giving. Copyright (C) 2010 John Wiley & Sons, Ltd.