Background: In community based immunization study availability of vaccination cards is critical but in most of the cases immunization cards are not found at home. Considering this, CORE Group Polio Project in Ethiopia distributed plastic bags for vaccination card handling integrated with child vaccination. Objective: Compare vaccination card retention rates between user and non-users of plastic bags Methods: Cross sectional study was conducted based on a random sample of 240 under two years children who had at least one dose of child vaccination and their caretakers from 24 Kebeles in Gambella region and Assosa Zone of B/Gumuz region. Data was collected at household level using face-to-face interview using interviewers who speak the local languages. Data was entered into EpiData and analyzed using STATA 12.0. Results: Overall vaccination card retention in both areas was 89.5% of which 64.5% got plastic bag. Of those who had plastic bag 91.2% presented child vaccination card inside the plastic bag. Vaccination card retention for households with plastic bag was 99.3% and for those with no plastic bag 76.0%, the difference was statistically significant (p<0.001). Unavailability of the plastic bag in the health facility at the time of vaccination was the main reason for not having it. Conclusion and recommendation: It is observed that availing plastic bag for caretakers will improve the rate of card retention at household level. Therefore, continuous refilling of plastic bags at the health facilities should be given priority if subsequent immunization based studies to get reliable information.