The aim of this study was to investigate how social responsibility marketing campaigns can be effective in branding for young millennials. An empirical model was applied in three specific cases of cause marketing targeting Generation Y. A total sample of 547 young people was obtained, and the data were analysed through the structural equation methodology using PLS data technical analysis. The results showed that, for millennials, marketing actions with a cause are effective in positioning the brands that carry them out favourably as long as requirements such as the alignment of their objectives with the social ideals and their closeness to millennials are met. Likewise, all the communication elements of the message will influence its effectiveness. This study provides new evidence on the attitudes of young millennials towards brands’ social marketing actions © 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/)