This study aimed to examine parents’ reactions (e.g., likes, comments) to a social media campaign encouraging participation in universal school meals (USM) programs, using a content analysis of parents’ reactions to static Facebook posts (images with captions) posted as part of a parent-directed campaign promoting USM participation. We calculated descriptive statistics of parents’ comments to characterize acceptance or rejection of campaign messages. Using thematic analysis, we inductively coded parents’ comments to identify themes associated with acceptance or rejection of the campaign messages. Comments indicating acceptance (34%) largely focused on gratitude for the money-saving, convenience, and social benefits of USM. Comments indicating rejection (29%) primarily discussed beliefs that school meals were unhealthy and of poor quality, with some questioning the posts’ credibility or seeking references or statistics to support the posts’ claims. Campaigns promoting USM may wish to focus on money-saving, convenience, and social benefits of USM, and include references and statistics to boost the credibility of claims.