Objective To determine whether a women's group intervention involving participatory learning and action has a sustainable and replicable effect on neonatal survival in rural, eastern India. Methods From 2004 to 2011, births and neonatal deaths in 36 geographical clusters in Jharkhand and Odisha were monitored. Between 2005 and 2008, these clusters were part of a randomized controlled trial of how women's group meetings involving participatory learning and action influence maternal and neonatal health. Between 2008 and 2011, groups in the original intervention clusters (zone1) continued to meet to discuss post-neonatal issues and new groups in the original control clusters (zone 2) met to discuss neonatal health. Logistic regression was used to examine neonatal mortality rates after 2008 in the two zones. Findings Data on 41 191 births were analysed. In zone 1, the intervention's effect was sustained: the cluster-mean neonatal mortality rate was 34.2 per 1000 live births (95% confidence interval, CI: 28.3-40.0) between 2008 and 2011, compared with 41.3 per 1000 live births (95% CI:35.4-47.1) between 2005 and 2008. The effect of the intervention was replicated in zone 2: the cluster-mean neonatal mortality rate decreased from 61.8 to 40.5 per 1000 live births between two periods: 2006-2008 and 2009-2011 (odds ratio: 0.69, 95%CI:0.57-0.83). Hygiene during delivery, thermal care of the neonate and exclusive breastfeeding were important factors. Conclusion The effect of participatory women's groups on neonatal survival in rural India, where neonatal mortality is high, was sustainable and replicable.