PurposeThe main purpose of this study is to contribute to the literature concerned with improving the effectiveness of corporate social responsibility (CSR) advertising by considering how such ads are pre-tested.Design/methodology/approachTwo similar video ads were produced: one using an informative appeal and the other using an emotional appeal. The latter appeal is more widely used by practitioners. Each ad was designed to promote the CSR credentials of the same (fictitious) company. A web-based experiment (n = 244) was used to test both using two types of measure: first attitude towards the company (such as its image) and second the feelings evoked by the ad.FindingsAs predicted from theory, the ads promoted similar evaluations of the company but the evaluations measured by evoked feelings differed significantly. The information-based ad evoked more positive emotions, less negative emotions and more positive attitudes toward the ad. If the ads had been pretested using only measures of evoked feelings, the more emotive treatment would have been rejected.Practical implicationsThe study shows why CSR ads should be pretested and why such tests should include multiple measures. It also illustrates how informative CSR video ads can be better received but how both informative and emotional appeals can be used when communicating a company's CSR.Originality/valueThere is little research relevant to the pretesting of ads designed to communicate a company's CSR. Signaling theory can help explain why comparable (CSR) video ads can be evaluated as similar in their effect on company related evaluations.