Vaccine-preventable diseases (VPD) are responsible for a significant portion of mortality across the life course in both low-income countries and in medium- and high-income countries. Yet, countries are consistently below the adult influenza vaccination targets, with rates in recent times even falling in some areas. (1) The study Towards Ending Immunization Inequity seeks to understand the various factors that contribute to the accessibility and effectiveness of vaccine-related messages and campaigns including the effects of social determinants, with the knowledge that these opportunities for communication represent a unique policy lever to improving uptake rates of vaccination in the most at-risk communities. (2) To address this knowledge gap, a 3-phase mixed-methods study was conducted including a preliminary scan of existing vaccine schedules and NITAG recommendations, focus groups and a cross-sectional survey. (3) Study results indicated that social determinants play a key role in an individual’s knowledge of vaccine-related information including types of vaccines available, vaccination gateways, vaccine recommendations and vaccine safety. (4) However, knowing that social determinants can influence uptake rates does not readily create opportunities and entry points for governments to implement tangible actions. An accessible entry point to reducing and ending immunization inequity is through changes in public health messaging to reach those who are currently unreachable.