Objective Long-term assessments of gatekeeper training (GKT) with multiple follow-ups are rare. Therefore, the aim of the current analysis is to examine 12-month follow-up outcomes of SafeTALK training in addition to the earlier analysis of pre-, post-, and 6-month follow-up. Method Two hundred and sixty two community volunteers participated in half-day (4-h) gatekeeper training sessions. Before, after, and 6- and 12-month follow-up surveys were used to assess participants’ knowledge, efficacy, and reluctance to intervene. Linear mixed effects regression was used in statistical analysis. Results Fifty six participants (21.4%) completed the 12-month follow-up, representing an attrition rate of 78.6% from pre-test. Linear mixed model analysis revealed a significant, consistent effect for time for knowledge, efficacy, and reluctance. Post-hoc testing revealed significant differences between scores at pre-test and 12-month follow-up for GK knowledge and efficacy; however, no significant difference was seen between these time points for reluctance to intervene. No significant change was measured between the 6 and 12 months for any outcomes. GK knowledge and efficacy remained significantly above pre-test scores. Conclusion The evaluation of the GKT demonstrated the long-term effectiveness of community-based suicide prevention training programs to improve and maintain GK knowledge and efficacy.