Given the increasing numbers of scandals, the awareness among fund-raisers that the public's trust is crucial for the nonprofit sector is growing. This study investigates the relationship between trust and charitable giving. Charitable organizations can increase the public's trust by signaling their trustworthiness. The example of the Netherlands shows how a system of accreditation can be an instrument for signaling trustworthiness to the public. Donors aware of the accreditation system have more trust in charities than those who are not aware, and they give more money to charitable causes. Charitable organizations have only limited control over the public's trust because it is also rooted in a general social trust in institutions and fellow citizens. It was shown that general social trust increases the amount people give to charitable causes, even more so when people know about the accreditation system. Finally, the conditions for introducing an accreditation system are discussed.