Theories of moral development posit that an internalized moral value that one should help those in need—the principle of care—evokes helping behaviour in situations where empathic concern does not. Examples of such situations are helping behaviours that involve cognitive deliberation and planning, that benefit others who are known only in the abstract, and who are out‐group members. Charitable giving to help people in need is an important helping behaviour that has these characteristics. Therefore we hypothesized that the principle of care would be positively associated with charitable giving to help people in need, and that the principle of care would mediate the empathic concern–giving relationship. The two hypotheses were tested across four studies. The studies used four different samples, including three nationally representative samples from the American and Dutch populations, and included both self‐reports of giving (Studies 1–3), giving observed in a survey experiment (Study 3), and giving observed in a laboratory experiment (Study 4). The evidence from these studies indicated that a moral principle to care for others was associated with charitable giving to help people in need and mediated the empathic concern–giving relationship. © 2016 The Authors. European Journal of Personality published by John Wiley & Sons Ltd on behalf of European Association of Personality Psychology