Objective The study aim was to test the acceptability and preliminary efficacy of a novel interactive web‐based breast reconstruction decision support aid (BRAID) for newly diagnosed breast cancer patients considering mastectomy. Methods Fifty‐five women considering mastectomy were randomly assigned to receive the BRAID versus the Cancer Support Community's Frankly Speaking About Cancer: Breast Reconstruction pamphlet. Participants completed measures of breast reconstruction (BR) knowledge, preparation to make a decision, decisional conflict, anxiety, and BR intentions before randomization and 2 weeks later. Results In terms of acceptability, enrollment into the study was satisfactory, but the rate of return for follow‐up surveys was lower among BRAID participants than pamphlet participants. Both interventions were evaluated favorably in terms of their value in facilitating the BR decision, and the majority of participants completing the follow‐up reported viewing the materials. In terms of preliminary efficacy, both interventions resulted in significant increases in BR knowledge and completeness and satisfaction with preparation to make a BR decision, and both interventions resulted in a significant reduction in decision conflict. However, there were no differences between interventions. Conclusion A widely available free pamphlet and a web‐based customized decision aid were highly utilized. The pamphlet was as effective in educating women about BR and prepared women equally as well to make the BR decision as compared with a more costly, customized web‐based decision support aid. Copyright © 2015 John Wiley & Sons, Ltd.