Objectives: WhatMakesUs is a digital media campaign aimed at reducing mental health stigma in the Greater Omaha-Council Bluffs metropolitan area. This study evaluated the campaign's impact at the end of the second year of the campaign by examining different aspects of mental health stigma, including social distance, attitudes, behaviours and self-efficacy, among campaign-aware (CA) individuals and non-campaign-aware (NCA) individuals. The study also explored the campaign's feasibility and potential for adaptation to other parts of the USA. Design, Setting, and Method: A cross-sectional online survey was conducted in the campaign's implementation area. Respondents were recruited through a panel recruiting company using non-probabilistic methods. Digital metrics from the campaign's social media accounts and website were collected and analysed using Google Analytics. Results: CA respondents exhibited lower social distance and stigmatising attitudes and beliefs, and more positive behaviours and self-efficacy towards people with mental health conditions (MHCs) compared to NCA respondents. A significantly higher proportion of CA respondents reported living with (p = 0.001), working with (p = 0.005), and having close friendships with individuals with MHCs (p = 0.043). CA respondents found therapy and counselling effective treatments for MHCs (p = 0.005), greater comfort in providing support to individuals with MHCs (p < 0.001), pursued steps to improve their own mental health (p = 0.032) and perceived their workplaces taking an active role in their mental health (p = 0.029), when compared to NCA respondents. Digital metrics indicated successful engagement with the campaign's intended audience. Conclusion: Findings highlight the impact of digital campaigns in addressing the stigmatisation of MHCs and provide valuable insights for future campaigns.