Vaccine hesitancy poses one of the largest threats to global health. Informing people about the collective benefit of vaccination has great potential in increasing vaccination intentions. This research investigates the potential for engaging experiences in immersive virtual reality (VR) to strengthen participants’ understanding of community immunity, and therefore, their intention to get vaccinated. In a pre-registered lab-in-the-field intervention study, participants were recruited in a public park (tested: n = 232, analyzed: n = 222). They were randomly assigned to experience the collective benefit of community immunity in a gamified immersive virtual reality environment (2/3 of sample), or to receive the same information via text and images (1/3 of sample). Before and after the intervention, participants indicated their intention to take up a hypothetical vaccine for a new COVID-19 strain (0–100 scale) and belief in vaccination as a collective responsibility (1–7 scale). The study employs a crossover design (participants later received a second treatment), but the primary outcome is the effect of the first treatment on vaccination intention. After the VR treatment, for participants with less-than-maximal vaccination intention, intention increases by 9.3 points (95% CI: 7.0 to 11.5, p < 0.001). The text-and- image treatment raises vaccination intention by 3.3 points (difference in effects: 5.8, 95% CI: 2.0 to 9.5, p = 0.003). The VR treatment also increases collective responsibility by 0.82 points (95% CI: 0.37 to 1.27, p < 0.001). The results suggest that VR interventions are an effective tool for boosting vaccination intention, and that they can be applied “in the wild”—providing a complementary method for vaccine advocacy.